picard-usbserial
PIC 16F1454 USB to Serial Adapter Firmware
/********************************************************************
File Information:
FileName: usb_device.c
Dependencies: See INCLUDES section
Processor: PIC18,PIC24, PIC32 and dsPIC33E USB Microcontrollers
Hardware: This code is natively intended to be used on Mirochip USB
demo boards. See www.microchip.com/usb (Software & Tools
section) for list of available platforms. The firmware may
be modified for use on other USB platforms by editing the
HardwareProfile.h and HardwareProfile - [platform].h files.
Complier: Microchip C18 (for PIC18),C30 (for PIC24 and dsPIC33E)
and C32 (for PIC32)
Company: Microchip Technology, Inc.
Software License Agreement:
The software supplied herewith by Microchip Technology Incorporated
(the "Company") for its PIC(r) Microcontroller is intended and
supplied to you, the Company's customer, for use solely and
exclusively on Microchip PIC Microcontroller products. The
software is owned by the Company and/or its supplier, and is
protected under applicable copyright laws. All rights are reserved.
Any use in violation of the foregoing restrictions may subject the
user to criminal sanctions under applicable laws, as well as to
civil liability for the breach of the terms and conditions of this
license.
THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION. NO WARRANTIES,
WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
Summary:
This file contains functions, macros, definitions, variables,
datatypes, etc. that are required for usage with the MCHPFSUSB device
stack. This file should be included in projects that use the device stack.
This file is located in the "\<Install Directory\>\\Microchip\\USB"
directory.
Description:
USB Device Stack File
This file contains functions, macros, definitions, variables,
datatypes, etc. that are required for usage with the MCHPFSUSB device
stack. This file should be included in projects that use the device stack.
This file is located in the "\<Install Directory\>\\Microchip\\USB"
directory.
When including this file in a new project, this file can either be
referenced from the directory in which it was installed or copied
directly into the user application folder. If the first method is
chosen to keep the file located in the folder in which it is installed
then include paths need to be added so that the library and the
application both know where to reference each others files. If the
application folder is located in the same folder as the Microchip
folder (like the current demo folders), then the following include
paths need to be added to the application's project:
.
..\\..\\MicrochipInclude
If a different directory structure is used, modify the paths as
required. An example using absolute paths instead of relative paths
would be the following:
C:\\Microchip Solutions\\Microchip\\Include
C:\\Microchip Solutions\\My Demo Application
********************************************************************
File Description:
Change History:
Rev Description
---- -----------
2.6 Added USBCancelIO() function. Moved and some stack
defintions to be more consistant with the host stack.
2.6a Fixed issue where a SET_CONFIGURATION received could cause
inability to transmit on an endpoint if using ping-pong
and an odd number of packets had been sent on that endpoint
2.7 Fixed error where the USB error interrupt flag was not getting
cleared properly for PIC32 resulting in lots of extra error interrupts.
http://www.microchip.com/forums/tm.aspx?m=479085
Fixed issue with dual role mode when device run in polling
mode. Interrupts were remaining enabled after the host mode
operation was complete. This was incompatible with polling
mode operation.
Changed how the bus sensing works. In previous revisions it
was impossible to use the USBDeviceDetach to detach from the
bus if the bus voltage was still present. This is now
possible. It was also possible to move the device to the
ATTACHED state in interrupt mode even if the bus voltage
wasn't available. This is now prohibited unless VBUS is
present.
Improved error case handling when the host sends more OUT
bytes in a control transfer than the firmware was expecting
to receive (based on the size parameter when calling USBEP0Receive()).
In the USBStdSetCfgHandler(), modified the code so the USBDeviceState
variable only gets updated to the CONFIGURED_STATE at the end of the
function.
2.7a Update to support the PIC18F47J53 A1 and later revision
devices.
Fixed an error on 16-bit and 32-bit processors where a word access
could be performed on a byte pointer resulting in possible address
errors with odd aligned pointers.
2.8 Several changes to the way control transfers get processed,
so as to support the ability to allow application/class specific
handler code to defer the status stage.
Implemented USBCtrlEPAllowStatusStage() API function.
Implemented USBDeferStatusStage() API function (macro).
These changes also greatly relax the USBDeviceTasks() calling frequency
requirement, while allowing USB class handlers more flexibility.
Also implemented the following API functions and macros, for delaying
the data stage of a control transfer (with data stage):
USBDeferINDataStage()
USBDeferOUTDataStage()
USBOUTDataStageDeferred()
USBINDataStageDeferred()
USBCtrlEPAllowDataStage()
Fixed USB reset event handler issue, where the USB stack would
re-initialize global interrupt settings in the interrupt context, on
PIC18 devices with the stack operated in USB_INTERRUPT mode.
Fixed handling of SET/CLEAR FEATURE (endpoint halt) host requests.
Previous implementation would not always initialize endpoints correctly
to DATA0 DTS state after a clear feature endpoint halt request, for
all ping pong mode and usage scenarios.
2.9 Fixed an issue with STALL handling behavior on non-EP0 endpoints, for
PIC24 and PIC32 devices.
Fixed an issue where the ep_data_in[]/ep_data_out[] flags weren't
getting re-initialized coincident with the hardware ping pong pointer
reset during set configuration events.
Implemented USBGetNextHandle() API function (actually a macro, defined
in usb_device.h).
2.9d Added build option for disabling DTS checking
2.9f Adding pragma for PIC18F97J94 Family BDT location.
2.9h Updated to be able to support optional Microsoft OS Descriptors
2.9i Updated to set UCON<SUSPND> bit on PIC16F USB devices during
suspend, so as to save power.
********************************************************************/
/*----------------------------------------------------------------------------------
The USBDeviceTasks() function is responsible for detecting and processing various
USB bus events and host requests, such as those required for USB enumeration, when
the USB cable is first attached to the host. This function is the main dispatcher
routine for the USB stack.
Additional API functions and macros are also provided by the USB stack, which can be
used to send/receive USB data to/from the host, among other things. A full list
of the available implemented functions/macros are provided in the
"MCHPFSUSB Library Help". For normal installations of the MCHPFSUSB Framework,
the USB API documentation can be found from:
Start menu --> (All Programs) --> Microchip --> MCHPFSUSB vX.x --> Documents --> MCHPFSUSB Library Help
Once the help file is opened, the API functions/macros are described in the following section:
Library Interface (API) --> Device/Peripheral --> Device Stack --> Interface Routines
Additional API functions may also be provided depending upon the specific USB device class
implemented, and these functions are also documented in the MCHPFSUSB Library Help.
If the USB stack is operated in "USB_POLLING" mode (user selectable option in
usb_config.h), then the application firmware is reponsible for calling the
USBDeviceTasks() function periodically. If the USB stack is operated in the
"USB_INTERRUPT" mode, then the application firmware does not have to directly
call USBDeviceTasks(), as it will execute only when necessary as an interrupt handler.
In order to properly operate a USB connection, and to correctly process and respond
to control transfers in the maximum time allowed by the USB specifications, the
USBDeviceTasks() function/interrupt handler must be allowed to execute in a timely
fashion.
When the USB module is enabled, the USB cable is attached to the host, the USB bus
is not in the suspend state, and the USB stack is operated in the USB_POLLING mode
with ping pong buffering enabled (at least) on EP0 OUT, then the maximum allowed
time between calls to the USBDeviceTasks() function needs to be:
The faster of:
1. Once per ~1.8ms, when USBDeviceState == ADR_PENDING_STATE
2. Once per ~9.8ms, when USBDeviceState == (any other value other than ADR_PENDING_STATE)
3. Fast enough to ensure the USTAT FIFO can never get full. See additional explanation below.
Additional details of the above timing limits are provided:
Timing item #1: This parameter originates from the 2ms set address "recovery interval"
specification dictated by section "9.2.6.3 Set Address Processing" of the official
USB 2.0 specifications.
Timing item #2: This parameter originates from several "10 ms" criteria in the
USB 2.0 specifications. For example, reset recovery intervals, resume recovery
intervals, suspend to actual current reduction, etc. have timing maximums of 10ms.
Timing item #3: This is not a fixed X.X ms parameter, but depends on the
transaction rate implemented by the application. The USBDeviceTasks() function is
responsible for popping entries off the USTAT FIFO. If the FIFO ever gets full,
then no further USB transactions are allowed to occur, until the firmware pops entries
off the FIFO. In practice, this means the firmware should call USBDeviceTasks() at
a rate at least as fast as once every three times the USBTransferOnePacket() function
is called. This ensures that the rate that USTAT FIFO entries are getting added to
the FIFO is lower than the rate that the entries are getting popped off the FIFO (the
USBDeviceTasks() function will pop up to 4 entries per call), which is a
necessary criteria to ensure the USTAT FIFO entries don't "pile up." Calling
USBDeviceTasks() even more often, ex: >=1 to 1 ratio of USBDeviceTasks() to
USBTransferOnePacket(), adds further protection against the USTAT FIFO getting full,
and is therefore recommended.
When the USB stack is operated in USB_INTERRUPT mode, then the above timing
parameters should be interpreted to be the longest allowed time that the USB
interrupts may be masked/disabled for, before re-enabling the USB interrupts.
Calling USBDeviceTasks() (or allowing USBDeviceTasks() to be called) more often
will still have potential USB data rate speed and processing latency benefits.
It is also beneficial to call USBDeviceTasks() more often than theoretically
required, since it has been observed that not all host/drivers/bios/hubs are
100% consistently compliant with all timing parameters of the USB 2.0 specifications.
Therefore, in a USB_POLLING based application, it is still suggested to call
USBDeviceTasks() as often as there are free CPU cycles. This ensures best
performance, along with best possible compatibility with all existing USB
hosts/hubs (both those that are compliant and [partially] non-compliant).
If ping pong buffering is not enabled on (at least) EP0 OUT, then it is required
to call (or allow to execute) USBDeviceTasks() much more frequently (ex: once
per 100us, or preferrably faster). Therefore, in all applications, it is
normally recommended to select either the USB_PING_PONG__FULL_PING_PONG or
USB_PING_PONG__EP0_OUT_ONLY mode (user option in usb_config.h), as these modes
allow for much more relaxed timing requirements, and therefore greater application
firmware design flexibility.
//----------------------------------------------------------------------------------*/
/** INCLUDES *******************************************************/
#include "./USB/usb.h"
#include "HardwareProfile.h"
#include "../USB/usb_device_local.h"
#if defined(USB_USE_MSD)
#include "./USB/usb_function_msd.h"
#endif
#if !defined(USE_USB_BUS_SENSE_IO)
#undef USB_BUS_SENSE
#define USB_BUS_SENSE 1
#endif
#if defined(USB_DEVICE_DISABLE_DTS_CHECKING)
#define _DTS_CHECKING_ENABLED 0
#else
#define _DTS_CHECKING_ENABLED _DTSEN
#endif
/** DEFINITIONS ****************************************************/
/** VARIABLES ******************************************************/
#if defined(__18CXX)
// #pragma udata
#endif
USB_VOLATILE USB_DEVICE_STATE USBDeviceState;
USB_VOLATILE BYTE USBActiveConfiguration;
USB_VOLATILE BYTE USBAlternateInterface[USB_MAX_NUM_INT];
volatile BDT_ENTRY *pBDTEntryEP0OutCurrent;
volatile BDT_ENTRY *pBDTEntryEP0OutNext;
volatile BDT_ENTRY *pBDTEntryOut[USB_MAX_EP_NUMBER+1];
volatile BDT_ENTRY *pBDTEntryIn[USB_MAX_EP_NUMBER+1];
USB_VOLATILE BYTE shortPacketStatus;
USB_VOLATILE BYTE controlTransferState;
USB_VOLATILE IN_PIPE inPipes[1];
USB_VOLATILE OUT_PIPE outPipes[1];
USB_VOLATILE BYTE *pDst;
USB_VOLATILE BOOL RemoteWakeup;
USB_VOLATILE BOOL USBBusIsSuspended;
USB_VOLATILE USTAT_FIELDS USTATcopy;
USB_VOLATILE BYTE endpoint_number;
USB_VOLATILE BOOL BothEP0OutUOWNsSet;
USB_VOLATILE EP_STATUS ep_data_in[USB_MAX_EP_NUMBER+1];
USB_VOLATILE EP_STATUS ep_data_out[USB_MAX_EP_NUMBER+1];
USB_VOLATILE BYTE USBStatusStageTimeoutCounter;
volatile BOOL USBDeferStatusStagePacket;
volatile BOOL USBStatusStageEnabledFlag1;
volatile BOOL USBStatusStageEnabledFlag2;
volatile BOOL USBDeferINDataStagePackets;
volatile BOOL USBDeferOUTDataStagePackets;
#if (USB_PING_PONG_MODE == USB_PING_PONG__NO_PING_PONG)
#define BDT_NUM_ENTRIES ((USB_MAX_EP_NUMBER + 1) * 2)
#elif (USB_PING_PONG_MODE == USB_PING_PONG__EP0_OUT_ONLY)
#define BDT_NUM_ENTRIES (((USB_MAX_EP_NUMBER + 1) * 2)+1)
#elif (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG)
#define BDT_NUM_ENTRIES ((USB_MAX_EP_NUMBER + 1) * 4)
#elif (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0)
#define BDT_NUM_ENTRIES (((USB_MAX_EP_NUMBER + 1) * 4)-2)
#else
#error "No ping pong mode defined."
#endif
/** USB FIXED LOCATION VARIABLES ***********************************/
#if defined(__18CXX)
// #pragma udata USB_BDT=USB_BDT_ADDRESS
#endif
volatile BDT_ENTRY BDT[BDT_NUM_ENTRIES] BDT_BASE_ADDR_TAG;
/********************************************************************
* Section B: EP0 Buffer Space
*******************************************************************/
volatile CTRL_TRF_SETUP SetupPkt CTRL_TRF_SETUP_ADDR_TAG;
volatile BYTE CtrlTrfData[USB_EP0_BUFF_SIZE] CTRL_TRF_DATA_ADDR_TAG;
/********************************************************************
* Section C: non-EP0 Buffer Space
*******************************************************************/
#if defined(USB_USE_MSD)
//volatile far USB_MSD_CBW_CSW msd_cbw_csw;
volatile USB_MSD_CBW msd_cbw;
volatile USB_MSD_CSW msd_csw;
//#pragma udata
#if defined(__18CXX)
#pragma udata myMSD=MSD_BUFFER_ADDRESS
#endif
volatile char msd_buffer[512];
#endif
////Depricated in v2.2 - will be removed in a future revision
#if !defined(USB_USER_DEVICE_DESCRIPTOR)
//Device descriptor
extern ROM USB_DEVICE_DESCRIPTOR device_dsc;
#else
USB_USER_DEVICE_DESCRIPTOR_INCLUDE;
#endif
#if !defined(USB_USER_CONFIG_DESCRIPTOR)
//Array of configuration descriptors
extern ROM BYTE *ROM USB_CD_Ptr[];
#else
USB_USER_CONFIG_DESCRIPTOR_INCLUDE;
#endif
extern ROM BYTE *ROM USB_SD_Ptr[];
/** DECLARATIONS ***************************************************/
#if defined(__18CXX)
// #pragma code
#endif
/** Macros *********************************************************/
/** Function Prototypes ********************************************/
//External
//This is the prototype for the required user event handler
BOOL USER_USB_CALLBACK_EVENT_HANDLER(int event, void *pdata, WORD size);
//Internal Functions
static void USBCtrlEPService(void);
static void USBCtrlTrfSetupHandler(void);
static void USBCtrlTrfInHandler(void);
static void USBCheckStdRequest(void);
static void USBStdGetDscHandler(void);
static void USBCtrlEPServiceComplete(void);
static void USBCtrlTrfTxService(void);
static void USBCtrlTrfRxService(void);
static void USBStdSetCfgHandler(void);
static void USBStdGetStatusHandler(void);
static void USBStdFeatureReqHandler(void);
static void USBCtrlTrfOutHandler(void);
static void USBConfigureEndpoint(BYTE EPNum, BYTE direction);
static void USBWakeFromSuspend(void);
static void USBSuspend(void);
static void USBStallHandler(void);
//static BOOL USBIsTxBusy(BYTE EPNumber);
//static void USBPut(BYTE EPNum, BYTE Data);
//static void USBEPService(void);
//static void USBProtocolResetHandler(void);
/******************************************************************************/
/** Function Implementations *************************************************/
/******************************************************************************/
/******************************************************************************/
/** Internal Macros *********************************************************/
/******************************************************************************/
/****************************************************************************
Function:
void USBAdvancePingPongBuffer(BDT_ENTRY** buffer)
Description:
This function will advance the passed pointer to the next buffer based on
the ping pong option setting. This function should be used for EP1-EP15
only. This function is not valid for EP0.
Precondition:
None
Parameters:
BDT_ENTRY** - pointer to the BDT_ENTRY pointer that you want to be advanced
to the next buffer state
Return Values:
None
Remarks:
None
***************************************************************************/
#define USBAdvancePingPongBuffer(buffer) ((BYTE_VAL*)buffer)->Val ^= USB_NEXT_PING_PONG;
#define USBHALPingPongSetToOdd(buffer) {((BYTE_VAL*)buffer)->Val |= USB_NEXT_PING_PONG;}
#define USBHALPingPongSetToEven(buffer) {((BYTE_VAL*)buffer)->Val &= ~USB_NEXT_PING_PONG;}
/******************************************************************************/
/** External API Functions ****************************************************/
/******************************************************************************/
/**************************************************************************
Function:
void USBDeviceInit(void)
Description:
This function initializes the device stack it in the default state. The
USB module will be completely reset including all of the internal
variables, registers, and interrupt flags.
Precondition:
This function must be called before any of the other USB Device
functions can be called, including USBDeviceTasks().
Parameters:
None
Return Values:
None
Remarks:
None
***************************************************************************/
void USBDeviceInit(void)
{
BYTE i;
USBDisableInterrupts();
// Clear all USB error flags
USBClearInterruptRegister(U1EIR);
// Clears all USB interrupts
USBClearInterruptRegister(U1IR);
//Clear all of the endpoint control registers
U1EP0 = 0;
DisableNonZeroEndpoints(USB_MAX_EP_NUMBER);
SetConfigurationOptions();
//power up the module (if not already powered)
USBPowerModule();
//set the address of the BDT (if applicable)
USBSetBDTAddress(BDT);
//Clear all of the BDT entries
for(i=0;i<(sizeof(BDT)/sizeof(BDT_ENTRY));i++)
{
BDT[i].Val = 0x00;
}
// Assert reset request to all of the Ping Pong buffer pointers
USBPingPongBufferReset = 1;
// Reset to default address
U1ADDR = 0x00;
// Make sure packet processing is enabled
USBPacketDisable = 0;
//Stop trying to reset ping pong buffer pointers
USBPingPongBufferReset = 0;
// Flush any pending transactions
while(USBTransactionCompleteIF == 1)
{
USBClearInterruptFlag(USBTransactionCompleteIFReg,USBTransactionCompleteIFBitNum);
//Initialize USB stack software state variables
inPipes[0].info.Val = 0;
outPipes[0].info.Val = 0;
outPipes[0].wCount.Val = 0;
}
//Set flags to TRUE, so the USBCtrlEPAllowStatusStage() function knows not to
//try and arm a status stage, even before the first control transfer starts.
USBStatusStageEnabledFlag1 = TRUE;
USBStatusStageEnabledFlag2 = TRUE;
//Initialize other flags
USBDeferINDataStagePackets = FALSE;
USBDeferOUTDataStagePackets = FALSE;
USBBusIsSuspended = FALSE;
//Initialize all pBDTEntryIn[] and pBDTEntryOut[]
//pointers to NULL, so they don't get used inadvertently.
for(i = 0; i < (BYTE)(USB_MAX_EP_NUMBER+1u); i++)
{
pBDTEntryIn[i] = 0u;
pBDTEntryOut[i] = 0u;
ep_data_in[i].Val = 0u;
ep_data_out[i].Val = 0u;
}
//Get ready for the first packet
pBDTEntryIn[0] = (volatile BDT_ENTRY*)&BDT[EP0_IN_EVEN];
// Initialize EP0 as a Ctrl EP
U1EP0 = EP_CTRL|USB_HANDSHAKE_ENABLED;
//Prepare for the first SETUP on EP0 OUT
BDT[EP0_OUT_EVEN].ADR = ConvertToPhysicalAddress(&SetupPkt);
BDT[EP0_OUT_EVEN].CNT = USB_EP0_BUFF_SIZE;
BDT[EP0_OUT_EVEN].STAT.Val = _USIE|_DAT0|_BSTALL;
// Clear active configuration
USBActiveConfiguration = 0;
//Indicate that we are now in the detached state
USBDeviceState = DETACHED_STATE;
}
/**************************************************************************
Function:
void USBDeviceTasks(void)
Summary:
This function is the main state machine/transaction handler of the USB
device side stack. When the USB stack is operated in "USB_POLLING" mode
(usb_config.h user option) the USBDeviceTasks() function should be called
periodically to receive and transmit packets through the stack. This
function also takes care of control transfers associated with the USB
enumeration process, and detecting various USB events (such as suspend).
This function should be called at least once every 1.8ms during the USB
enumeration process. After the enumeration process is complete (which can
be determined when USBGetDeviceState() returns CONFIGURED_STATE), the
USBDeviceTasks() handler may be called the faster of: either once
every 9.8ms, or as often as needed to make sure that the hardware USTAT
FIFO never gets full. A good rule of thumb is to call USBDeviceTasks() at
a minimum rate of either the frequency that USBTransferOnePacket() gets
called, or, once/1.8ms, whichever is faster. See the inline code comments
near the top of usb_device.c for more details about minimum timing
requirements when calling USBDeviceTasks().
When the USB stack is operated in "USB_INTERRUPT" mode, it is not necessary
to call USBDeviceTasks() from the main loop context. In the USB_INTERRUPT
mode, the USBDeviceTasks() handler only needs to execute when a USB
interrupt occurs, and therefore only needs to be called from the interrupt
context.
Description:
This function is the main state machine/transaction handler of the USB
device side stack. When the USB stack is operated in "USB_POLLING" mode
(usb_config.h user option) the USBDeviceTasks() function should be called
periodically to receive and transmit packets through the stack. This
function also takes care of control transfers associated with the USB
enumeration process, and detecting various USB events (such as suspend).
This function should be called at least once every 1.8ms during the USB
enumeration process. After the enumeration process is complete (which can
be determined when USBGetDeviceState() returns CONFIGURED_STATE), the
USBDeviceTasks() handler may be called the faster of: either once
every 9.8ms, or as often as needed to make sure that the hardware USTAT
FIFO never gets full. A good rule of thumb is to call USBDeviceTasks() at
a minimum rate of either the frequency that USBTransferOnePacket() gets
called, or, once/1.8ms, whichever is faster. See the inline code comments
near the top of usb_device.c for more details about minimum timing
requirements when calling USBDeviceTasks().
When the USB stack is operated in "USB_INTERRUPT" mode, it is not necessary
to call USBDeviceTasks() from the main loop context. In the USB_INTERRUPT
mode, the USBDeviceTasks() handler only needs to execute when a USB
interrupt occurs, and therefore only needs to be called from the interrupt
context.
Typical usage:
<code>
void main(void)
{
USBDeviceInit();
while(1)
{
USBDeviceTasks(); //Takes care of enumeration and other USB events
if((USBGetDeviceState() \< CONFIGURED_STATE) ||
(USBIsDeviceSuspended() == TRUE))
{
//Either the device is not configured or we are suspended,
// so we don't want to execute any USB related application code
continue; //go back to the top of the while loop
}
else
{
//Otherwise we are free to run USB and non-USB related user
//application code.
UserApplication();
}
}
}
</code>
Precondition:
Make sure the USBDeviceInit() function has been called prior to calling
USBDeviceTasks() for the first time.
Remarks:
USBDeviceTasks() does not need to be called while in the USB suspend mode,
if the user application firmware in the USBCBSuspend() callback function
enables the ACTVIF USB interrupt source and put the microcontroller into
sleep mode. If the application firmware decides not to sleep the
microcontroller core during USB suspend (ex: continues running at full
frequency, or clock switches to a lower frequency), then the USBDeviceTasks()
function must still be called periodically, at a rate frequent enough to
ensure the 10ms resume recovery interval USB specification is met. Assuming
a worst case primary oscillator and PLL start up time of <5ms, then
USBDeviceTasks() should be called once every 5ms in this scenario.
When the USB cable is detached, or the USB host is not actively powering
the VBUS line to +5V nominal, the application firmware does not always have
to call USBDeviceTasks() frequently, as no USB activity will be taking
place. However, if USBDeviceTasks() is not called regularly, some
alternative means of promptly detecting when VBUS is powered (indicating
host attachment), or not powered (host powered down or USB cable unplugged)
is still needed. For self or dual self/bus powered USB applications, see
the USBDeviceAttach() and USBDeviceDetach() API documentation for additional
considerations.
**************************************************************************/
#if defined(USB_INTERRUPT)
#if defined(__18CXX) || defined (_PIC14E)
void USBDeviceTasks(void)
#elif defined(__C30__) || defined __XC16__
void __attribute__((interrupt,auto_psv)) _USB1Interrupt()
#elif defined(__PIC32MX__)
void __attribute__((interrupt(),vector(_USB_1_VECTOR))) _USB1Interrupt( void )
#endif
#else
void USBDeviceTasks(void)
#endif
{
BYTE i;
#ifdef USB_SUPPORT_OTG
//SRP Time Out Check
if (USBOTGSRPIsReady())
{
if (USBT1MSECIF && USBT1MSECIE)
{
if (USBOTGGetSRPTimeOutFlag())
{
if (USBOTGIsSRPTimeOutExpired())
{
USB_OTGEventHandler(0,OTG_EVENT_SRP_FAILED,0,0);
}
}
//Clear Interrupt Flag
USBClearInterruptFlag(USBT1MSECIFReg,USBT1MSECIFBitNum);
}
}
#endif
#if defined(USB_POLLING)
//If the interrupt option is selected then the customer is required
// to notify the stack when the device is attached or removed from the
// bus by calling the USBDeviceAttach() and USBDeviceDetach() functions.
if (USB_BUS_SENSE != 1)
{
// Disable module & detach from bus
U1CON = 0;
// Mask all USB interrupts
U1IE = 0;
//Move to the detached state
USBDeviceState = DETACHED_STATE;
#ifdef USB_SUPPORT_OTG
//Disable D+ Pullup
U1OTGCONbits.DPPULUP = 0;
//Disable HNP
USBOTGDisableHnp();
//Deactivate HNP
USBOTGDeactivateHnp();
//If ID Pin Changed State
if (USBIDIF && USBIDIE)
{
//Re-detect & Initialize
USBOTGInitialize();
//Clear ID Interrupt Flag
USBClearInterruptFlag(USBIDIFReg,USBIDIFBitNum);
}
#endif
#if defined __C30__ || defined __XC16__
//USBClearInterruptFlag(U1OTGIR, 3);
#endif
//return so that we don't go through the rest of
//the state machine
USBClearUSBInterrupt();
return;
}
#ifdef USB_SUPPORT_OTG
//If Session Is Started Then
else
{
//If SRP Is Ready
if (USBOTGSRPIsReady())
{
//Clear SRPReady
USBOTGClearSRPReady();
//Clear SRP Timeout Flag
USBOTGClearSRPTimeOutFlag();
//Indicate Session Started
UART2PrintString( "\r\n***** USB OTG B Event - Session Started *****\r\n" );
}
}
#endif //#ifdef USB_SUPPORT_OTG
//if we are in the detached state
if(USBDeviceState == DETACHED_STATE)
{
//Initialize register to known value
U1CON = 0;
// Mask all USB interrupts
U1IE = 0;
//Enable/set things like: pull ups, full/low-speed mode,
//set the ping pong mode, and set internal transceiver
SetConfigurationOptions();
// Enable module & attach to bus
while(!U1CONbits.USBEN){U1CONbits.USBEN = 1;}
//moved to the attached state
USBDeviceState = ATTACHED_STATE;
#ifdef USB_SUPPORT_OTG
U1OTGCON |= USB_OTG_DPLUS_ENABLE | USB_OTG_ENABLE;
#endif
}
#endif //#if defined(USB_POLLING)
if(USBDeviceState == ATTACHED_STATE)
{
/*
* After enabling the USB module, it takes some time for the
* voltage on the D+ or D- line to rise high enough to get out
* of the SE0 condition. The USB Reset interrupt should not be
* unmasked until the SE0 condition is cleared. This helps
* prevent the firmware from misinterpreting this unique event
* as a USB bus reset from the USB host.
*/
if(!USBSE0Event)
{
USBClearInterruptRegister(U1IR);// Clear all USB interrupts
#if defined(USB_POLLING)
U1IE=0; // Mask all USB interrupts
#endif
USBResetIE = 1; // Unmask RESET interrupt
USBIdleIE = 1; // Unmask IDLE interrupt
USBDeviceState = POWERED_STATE;
}
}
#ifdef USB_SUPPORT_OTG
//If ID Pin Changed State
if (USBIDIF && USBIDIE)
{
//Re-detect & Initialize
USBOTGInitialize();
USBClearInterruptFlag(USBIDIFReg,USBIDIFBitNum);
}
#endif
/*
* Task A: Service USB Activity Interrupt
*/
if(USBActivityIF && USBActivityIE)
{
USBClearInterruptFlag(USBActivityIFReg,USBActivityIFBitNum);
#if defined(USB_SUPPORT_OTG)
U1OTGIR = 0x10;
#else
USBWakeFromSuspend();
#endif
}
/*
* Pointless to continue servicing if the device is in suspend mode.
*/
if(USBSuspendControl==1)
{
USBClearUSBInterrupt();
return;
}
/*
* Task B: Service USB Bus Reset Interrupt.
* When bus reset is received during suspend, ACTVIF will be set first,
* once the UCONbits.SUSPND is clear, then the URSTIF bit will be asserted.
* This is why URSTIF is checked after ACTVIF.
*
* The USB reset flag is masked when the USB state is in
* DETACHED_STATE or ATTACHED_STATE, and therefore cannot
* cause a USB reset event during these two states.
*/
if(USBResetIF && USBResetIE)
{
USBDeviceInit();
//Re-enable the interrupts since the USBDeviceInit() function will
// disable them. This will do nothing in a polling setup
USBUnmaskInterrupts();
USBDeviceState = DEFAULT_STATE;
#ifdef USB_SUPPORT_OTG
//Disable HNP
USBOTGDisableHnp();
//Deactivate HNP
USBOTGDeactivateHnp();
#endif
USBClearInterruptFlag(USBResetIFReg,USBResetIFBitNum);
}
/*
* Task C: Service other USB interrupts
*/
if(USBIdleIF && USBIdleIE)
{
#ifdef USB_SUPPORT_OTG
//If Suspended, Try to switch to Host
USBOTGSelectRole(ROLE_HOST);
#else
USBSuspend();
#endif
USBClearInterruptFlag(USBIdleIFReg,USBIdleIFBitNum);
}
if(USBSOFIF)
{
if(USBSOFIE)
{
USB_SOF_HANDLER(EVENT_SOF,0,1);
}
USBClearInterruptFlag(USBSOFIFReg,USBSOFIFBitNum);
#if defined(USB_ENABLE_STATUS_STAGE_TIMEOUTS)
//Supporting this feature requires a 1ms timebase for keeping track of the timeout interval.
#if(USB_SPEED_OPTION == USB_LOW_SPEED)
#warning "Double click this message. See inline code comments."
//The "USB_ENABLE_STATUS_STAGE_TIMEOUTS" feature is optional and is
//not strictly needed in all applications (ex: those that never call
//USBDeferStatusStage() and don't use host to device (OUT) control
//transfers with data stage).
//However, if this feature is enabled and used, it requires a timer
//(preferrably 1ms) to decrement the USBStatusStageTimeoutCounter.
//In USB Full Speed applications, the host sends Start-of-Frame (SOF)
//packets at a 1ms rate, which generates SOFIF interrupts.
//These interrupts can be used to decrement USBStatusStageTimeoutCounter as shown
//below. However, the host does not send SOF packets to Low Speed devices.
//Therefore, some other method (ex: using a general purpose microcontroller
//timer, such as Timer0) needs to be implemented to call and execute the below code
//at a once/1ms rate, in a low speed USB application.
//Note: Pre-condition to executing the below code: USBDeviceInit() should have
//been called at least once (since the last microcontroller reset/power up),
//prior to executing the below code.
#endif
//Decrement our status stage counter.
if(USBStatusStageTimeoutCounter != 0u)
{
USBStatusStageTimeoutCounter--;
}
//Check if too much time has elapsed since progress was made in
//processing the control transfer, without arming the status stage.
//If so, auto-arm the status stage to ensure that the control
//transfer can [eventually] complete, within the timing limits
//dictated by section 9.2.6 of the official USB 2.0 specifications.
if(USBStatusStageTimeoutCounter == 0)
{
USBCtrlEPAllowStatusStage(); //Does nothing if the status stage was already armed.
}
#endif
}
if(USBStallIF && USBStallIE)
{
USBStallHandler();
}
if(USBErrorIF && USBErrorIE)
{
USB_ERROR_HANDLER(EVENT_BUS_ERROR,0,1);
USBClearInterruptRegister(U1EIR); // This clears UERRIF
//On PIC18, clearing the source of the error will automatically clear
// the interrupt flag. On other devices the interrupt flag must be
// manually cleared.
#if defined(__C32__) || defined(__C30__) || defined __XC16__
USBClearInterruptFlag( USBErrorIFReg, USBErrorIFBitNum );
#endif
}
/*
* Pointless to continue servicing if the host has not sent a bus reset.
* Once bus reset is received, the device transitions into the DEFAULT
* state and is ready for communication.
*/
if(USBDeviceState < DEFAULT_STATE)
{
USBClearUSBInterrupt();
return;
}
/*
* Task D: Servicing USB Transaction Complete Interrupt
*/
if(USBTransactionCompleteIE)
{
for(i = 0; i < 4u; i++) //Drain or deplete the USAT FIFO entries. If the USB FIFO ever gets full, USB bandwidth
{ //utilization can be compromised, and the device won't be able to receive SETUP packets.
if(USBTransactionCompleteIF)
{
//Save and extract USTAT register info. Will use this info later.
USTATcopy.Val = U1STAT;
endpoint_number = USBHALGetLastEndpoint(USTATcopy);
USBClearInterruptFlag(USBTransactionCompleteIFReg,USBTransactionCompleteIFBitNum);
//Keep track of the hardware ping pong state for endpoints other
//than EP0, if ping pong buffering is enabled.
#if (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0) || (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG)
if(USBHALGetLastDirection(USTATcopy) == OUT_FROM_HOST)
{
ep_data_out[endpoint_number].bits.ping_pong_state ^= 1;
}
else
{
ep_data_in[endpoint_number].bits.ping_pong_state ^= 1;
}
#endif
//USBCtrlEPService only services transactions over EP0.
//It ignores all other EP transactions.
if(endpoint_number == 0)
{
USBCtrlEPService();
}
else
{
USB_TRANSFER_COMPLETE_HANDLER(EVENT_TRANSFER, (BYTE*)&USTATcopy.Val, 0);
}
}//end if(USBTransactionCompleteIF)
else
break; //USTAT FIFO must be empty.
}//end for()
}//end if(USBTransactionCompleteIE)
USBClearUSBInterrupt();
}//end of USBDeviceTasks()
/*******************************************************************************
Function:
void USBEnableEndpoint(BYTE ep, BYTE options)
Summary:
This function will enable the specified endpoint with the specified
options
Description:
This function will enable the specified endpoint with the specified
options.
Typical Usage:
<code>
void USBCBInitEP(void)
{
USBEnableEndpoint(MSD_DATA_IN_EP,USB_IN_ENABLED|USB_OUT_ENABLED|USB_HANDSHAKE_ENABLED|USB_DISALLOW_SETUP);
USBMSDInit();
}
</code>
In the above example endpoint number MSD_DATA_IN_EP is being configured
for both IN and OUT traffic with handshaking enabled. Also since
MSD_DATA_IN_EP is not endpoint 0 (MSD does not allow this), then we can
explicitly disable SETUP packets on this endpoint.
Conditions:
None
Input:
BYTE ep - the endpoint to be configured
BYTE options - optional settings for the endpoint. The options should
be ORed together to form a single options string. The
available optional settings for the endpoint. The
options should be ORed together to form a single options
string. The available options are the following\:
* USB_HANDSHAKE_ENABLED enables USB handshaking (ACK,
NAK)
* USB_HANDSHAKE_DISABLED disables USB handshaking (ACK,
NAK)
* USB_OUT_ENABLED enables the out direction
* USB_OUT_DISABLED disables the out direction
* USB_IN_ENABLED enables the in direction
* USB_IN_DISABLED disables the in direction
* USB_ALLOW_SETUP enables control transfers
* USB_DISALLOW_SETUP disables control transfers
* USB_STALL_ENDPOINT STALLs this endpoint
Return:
None
Remarks:
None
*****************************************************************************/
void USBEnableEndpoint(BYTE ep, BYTE options)
{
unsigned char* p;
//Use USBConfigureEndpoint() to set up the pBDTEntryIn/Out[ep] pointer and
//starting DTS state in the BDT entry.
if(options & USB_OUT_ENABLED)
{
USBConfigureEndpoint(ep, OUT_FROM_HOST);
}
if(options & USB_IN_ENABLED)
{
USBConfigureEndpoint(ep, IN_TO_HOST);
}
//Update the relevant UEPx register to actually enable the endpoint with
//the specified options (ex: handshaking enabled, control transfers allowed,
//etc.)
#if defined(__C32__)
p = (unsigned char*)(&U1EP0+(4*ep));
#else
p = (unsigned char*)(&U1EP0+ep);
#endif
*p = options;
}
/*************************************************************************
Function:
USB_HANDLE USBTransferOnePacket(BYTE ep, BYTE dir, BYTE* data, BYTE len)
Summary:
Transfers a single packet (one transaction) of data on the USB bus.
Description:
The USBTransferOnePacket() function prepares a USB endpoint
so that it may send data to the host (an IN transaction), or
receive data from the host (an OUT transaction). The
USBTransferOnePacket() function can be used both to receive and
send data to the host. This function is the primary API function
provided by the USB stack firmware for sending or receiving application
data over the USB port.
The USBTransferOnePacket() is intended for use with all application
endpoints. It is not used for sending or receiving applicaiton data
through endpoint 0 by using control transfers. Separate API
functions, such as USBEP0Receive(), USBEP0SendRAMPtr(), and
USBEP0SendROMPtr() are provided for this purpose.
The USBTransferOnePacket() writes to the Buffer Descriptor Table (BDT)
entry associated with an endpoint buffer, and sets the UOWN bit, which
prepares the USB hardware to allow the transaction to complete. The
application firmware can use the USBHandleBusy() macro to check the
status of the transaction, to see if the data has been successfully
transmitted yet.
Typical Usage
<code>
//make sure that the we are in the configured state
if(USBGetDeviceState() == CONFIGURED_STATE)
{
//make sure that the last transaction isn't busy by checking the handle
if(!USBHandleBusy(USBInHandle))
{
//Write the new data that we wish to send to the host to the INPacket[] array
INPacket[0] = USEFUL_APPLICATION_VALUE1;
INPacket[1] = USEFUL_APPLICATION_VALUE2;
//INPacket[2] = ... (fill in the rest of the packet data)
//Send the data contained in the INPacket[] array through endpoint "EP_NUM"
USBInHandle = USBTransferOnePacket(EP_NUM,IN_TO_HOST,(BYTE*)&INPacket[0],sizeof(INPacket));
}
}
</code>
Conditions:
Before calling USBTransferOnePacket(), the following should be true.
1. The USB stack has already been initialized (USBDeviceInit() was called).
2. A transaction is not already pending on the specified endpoint. This
is done by checking the previous request using the USBHandleBusy()
macro (see the typical usage example).
3. The host has already sent a set configuration request and the
enumeration process is complete.
This can be checked by verifying that the USBGetDeviceState()
macro returns "CONFIGURED_STATE", prior to calling
USBTransferOnePacket().
Input:
BYTE ep - The endpoint number that the data will be transmitted or
received on
BYTE dir - The direction of the transfer
This value is either OUT_FROM_HOST or IN_TO_HOST
BYTE* data - For IN transactions: pointer to the RAM buffer containing
the data to be sent to the host. For OUT transactions: pointer
to the RAM buffer that the received data should get written to.
BYTE len - Length of the data needing to be sent (for IN transactions).
For OUT transactions, the len parameter should normally be set
to the endpoint size specified in the endpoint descriptor.
Return Values:
USB_HANDLE - handle to the transfer. The handle is a pointer to
the BDT entry associated with this transaction. The
status of the transaction (ex: if it is complete or still
pending) can be checked using the USBHandleBusy() macro
and supplying the USB_HANDLE provided by
USBTransferOnePacket().
Remarks:
If calling the USBTransferOnePacket() function from within the USBCBInitEP()
callback function, the set configuration is still being processed and the
USBDeviceState may not be == CONFIGURED_STATE yet. In this special case,
the USBTransferOnePacket() may still be called, but make sure that the
endpoint has been enabled and initialized by the USBEnableEndpoint()
function first.
*************************************************************************/
USB_HANDLE USBTransferOnePacket(BYTE ep,BYTE dir,BYTE* data,BYTE len)
{
volatile BDT_ENTRY* handle;
//If the direction is IN
if(dir != 0)
{
//point to the IN BDT of the specified endpoint
handle = pBDTEntryIn[ep];
}
else
{
//else point to the OUT BDT of the specified endpoint
handle = pBDTEntryOut[ep];
}
//Error checking code. Make sure the handle (pBDTEntryIn[ep] or
//pBDTEntryOut[ep]) is initialized before using it.
if(handle == 0)
{
return 0;
}
//Toggle the DTS bit if required
#if (USB_PING_PONG_MODE == USB_PING_PONG__NO_PING_PONG)
handle->STAT.Val ^= _DTSMASK;
#elif (USB_PING_PONG_MODE == USB_PING_PONG__EP0_OUT_ONLY)
if(ep != 0)
{
handle->STAT.Val ^= _DTSMASK;
}
#endif
//Set the data pointer, data length, and enable the endpoint
handle->ADR = ConvertToPhysicalAddress(data);
handle->CNT = len;
handle->STAT.Val &= _DTSMASK;
handle->STAT.Val |= _USIE | (_DTSEN & _DTS_CHECKING_ENABLED);
//Point to the next buffer for ping pong purposes.
if(dir != OUT_FROM_HOST)
{
//toggle over the to the next buffer for an IN endpoint
USBAdvancePingPongBuffer(&pBDTEntryIn[ep]);
}
else
{
//toggle over the to the next buffer for an OUT endpoint
USBAdvancePingPongBuffer(&pBDTEntryOut[ep]);
}
return (USB_HANDLE)handle;
}
/********************************************************************
Function:
void USBStallEndpoint(BYTE ep, BYTE dir)
Summary:
Configures the specified endpoint to send STALL to the host, the next
time the host tries to access the endpoint.
PreCondition:
None
Parameters:
BYTE ep - The endpoint number that should be configured to send STALL.
BYTE dir - The direction of the endpoint to STALL, either
IN_TO_HOST or OUT_FROM_HOST.
Return Values:
None
Remarks:
None
*******************************************************************/
void USBStallEndpoint(BYTE ep, BYTE dir)
{
BDT_ENTRY *p;
if(ep == 0)
{
//For control endpoints (ex: EP0), we need to STALL both IN and OUT
//endpoints. EP0 OUT must also be prepared to receive the next SETUP
//packet that will arrrive.
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&SetupPkt);
pBDTEntryEP0OutNext->STAT.Val = _USIE|_DAT0|(_DTSEN & _DTS_CHECKING_ENABLED)|_BSTALL;
pBDTEntryIn[0]->STAT.Val = _USIE|_BSTALL;
}
else
{
p = (BDT_ENTRY*)(&BDT[EP(ep,dir,0)]);
p->STAT.Val |= _BSTALL | _USIE;
//If the device is in FULL or ALL_BUT_EP0 ping pong modes
//then stall that entry as well
#if (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG) || (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0)
p = (BDT_ENTRY*)(&BDT[EP(ep,dir,1)]);
p->STAT.Val |= _BSTALL | _USIE;
#endif
}
}
/**************************************************************************
Function:
void USBCancelIO(BYTE endpoint)
Description:
This function cancels the transfers pending on the specified endpoint.
This function can only be used after a SETUP packet is received and
before that setup packet is handled. This is the time period in which
the EVENT_EP0_REQUEST is thrown, before the event handler function
returns to the stack.
Precondition:
Parameters:
BYTE endpoint - the endpoint number you wish to cancel the transfers for
Return Values:
None
Remarks:
None
**************************************************************************/
void USBCancelIO(BYTE endpoint)
{
if(USBPacketDisable == 1)
{
//The PKTDIS bit is currently set right now. It is therefore "safe"
//to mess with the BDT right now.
pBDTEntryIn[endpoint]->Val &= _DTSMASK; //Makes UOWN = 0 (_UCPU mode). Deactivates endpoint. Only sends NAKs.
pBDTEntryIn[endpoint]->Val ^= _DTSMASK; //Toggle the DTS bit. This packet didn't get sent yet, and the next call to USBTransferOnePacket() will re-toggle the DTS bit back to the original (correct) value.
//Need to do additional handling if ping-pong buffering is being used
#if ((USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG) || (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0))
//Point to the next buffer for ping pong purposes. UOWN getting cleared
//(either due to SIE clearing it after a transaction, or the firmware
//clearing it) makes hardware ping pong pointer advance.
USBAdvancePingPongBuffer(&pBDTEntryIn[endpoint]);
pBDTEntryIn[endpoint]->STAT.Val &= _DTSMASK;
pBDTEntryIn[endpoint]->STAT.Val ^= _DTSMASK;
#endif
}
}
/**************************************************************************
Function:
void USBDeviceDetach(void)
Summary:
This function configures the USB module to "soft detach" itself from
the USB host.
Description:
This function configures the USB module to perform a "soft detach"
operation, by disabling the D+ (or D-) ~1.5k pull up resistor, which
lets the host know the device is present and attached. This will make
the host think that the device has been unplugged. This is potentially
useful, as it allows the USB device to force the host to re-enumerate
the device (on the firmware has re-enabled the USB module/pull up, by
calling USBDeviceAttach(), to "soft re-attach" to the host).
Precondition:
Should only be called when USB_INTERRUPT is defined. See remarks
section if USB_POLLING mode option is being used (usb_config.h option).
Additionally, this function should only be called from the main() loop
context. Do not call this function from within an interrupt handler, as
this function may modify global interrupt enable bits and settings.
Parameters:
None
Return Values:
None
Remarks:
If the application firmware calls USBDeviceDetach(), it is strongly
recommended that the firmware wait at least >= 80ms before calling
USBDeviceAttach(). If the firmeware performs a soft detach, and then
re-attaches too soon (ex: after a few micro seconds for instance), some
hosts may interpret this as an unexpected "glitch" rather than as a
physical removal/re-attachment of the USB device. In this case the host
may simply ignore the event without re-enumerating the device. To
ensure that the host properly detects and processes the device soft
detach/re-attach, it is recommended to make sure the device remains
detached long enough to mimic a real human controlled USB
unplug/re-attach event (ex: after calling USBDeviceDetach(), do not
call USBDeviceAttach() for at least 80+ms, preferrably longer.
Neither the USBDeviceDetach() or USBDeviceAttach() functions are blocking
or take long to execute. It is the application firmware's
responsibility for adding the 80+ms delay, when using these API
functions.
Note: The Windows plug and play event handler processing is fairly
slow, especially in certain versions of Windows, and for certain USB
device classes. It has been observed that some device classes need to
provide even more USB detach dwell interval (before calling
USBDeviceAttach()), in order to work correctly after re-enumeration.
If the USB device is a CDC class device, it is recommended to wait
at least 1.5 seconds or longer, before soft re-attaching to the host,
to provide the plug and play event handler enough time to finish
processing the removal event, before the re-attach occurs.
If the application is using the USB_POLLING mode option, then the
USBDeviceDetach() and USBDeviceAttach() functions are not available.
In this mode, the USB stack relies on the "#define USE_USB_BUS_SENSE_IO"
and "#define USB_BUS_SENSE" options in the
HardwareProfile – [platform name].h file.
When using the USB_POLLING mode option, and the
"#define USE_USB_BUS_SENSE_IO" definition has been commented out, then
the USB stack assumes that it should always enable the USB module at
pretty much all times. Basically, anytime the application firmware
calls USBDeviceTasks(), the firmware will automatically enable the USB
module. This mode would typically be selected if the application was
designed to be a purely bus powered device. In this case, the
application is powered from the +5V VBUS supply from the USB port, so
it is correct and sensible in this type of application to power up and
turn on the USB module, at anytime that the microcontroller is
powered (which implies the USB cable is attached and the host is also
powered).
In a self powered application, the USB stack is designed with the
intention that the user will enable the "#define USE_USB_BUS_SENSE_IO"
option in the HardwareProfile – [platform name].h file. When this
option is defined, then the USBDeviceTasks() function will automatically
check the I/O pin port value of the designated pin (based on the
#define USB_BUS_SENSE option in the HardwareProfile – [platform name].h
file), every time the application calls USBDeviceTasks(). If the
USBDeviceTasks() function is executed and finds that the pin defined by
the #define USB_BUS_SENSE is in a logic low state, then it will
automatically disable the USB module and tri-state the D+ and D- pins.
If however the USBDeviceTasks() function is executed and finds the pin
defined by the #define USB_BUS_SENSE is in a logic high state, then it
will automatically enable the USB module, if it has not already been
enabled.
**************************************************************************/
#if defined(USB_INTERRUPT)
void USBDeviceDetach(void)
{
//If the interrupt option is selected then the customer is required
// to notify the stack when the device is attached or removed from the
// bus by calling the USBDeviceAttach() and USBDeviceDetach() functions.
#ifdef USB_SUPPORT_OTG
if (USB_BUS_SENSE != 1)
#endif
{
// Disable module & detach from bus
U1CON = 0;
// Mask all USB interrupts
U1IE = 0;
//Move to the detached state
USBDeviceState = DETACHED_STATE;
#ifdef USB_SUPPORT_OTG
//Disable D+ Pullup
U1OTGCONbits.DPPULUP = 0;
//Disable HNP
USBOTGDisableHnp();
//Deactivate HNP
USBOTGDeactivateHnp();
//If ID Pin Changed State
if (USBIDIF && USBIDIE)
{
//Re-detect & Initialize
USBOTGInitialize();
//Clear ID Interrupt Flag
USBClearInterruptFlag(USBIDIFReg,USBIDIFBitNum);
}
#endif
#if defined __C30__ || defined __XC16__
//USBClearInterruptFlag(U1OTGIR, 3);
#endif
//return so that we don't go through the rest of
//the state machine
return;
}
#ifdef USB_SUPPORT_OTG
//If Session Is Started Then
else
{
//If SRP Is Ready
if (USBOTGSRPIsReady())
{
//Clear SRPReady
USBOTGClearSRPReady();
//Clear SRP Timeout Flag
USBOTGClearSRPTimeOutFlag();
//Indicate Session Started
UART2PrintString( "\r\n***** USB OTG B Event - Session Started *****\r\n" );
}
}
#endif
}
#endif //#if defined(USB_INTERRUPT)
/**************************************************************************
Function:
void USBDeviceAttach(void)
Summary:
Checks if VBUS is present, and that the USB module is not already
initalized, and if so, enables the USB module so as to signal device
attachment to the USB host.
Description:
This function indicates to the USB host that the USB device has been
attached to the bus. This function needs to be called in order for the
device to start to enumerate on the bus.
Precondition:
Should only be called when USB_INTERRUPT is defined. Also, should only
be called from the main() loop context. Do not call USBDeviceAttach()
from within an interrupt handler, as the USBDeviceAttach() function
may modify global interrupt enable bits and settings.
For normal USB devices:
Make sure that if the module was previously on, that it has been turned off
for a long time (ex: 100ms+) before calling this function to re-enable the module.
If the device turns off the D+ (for full speed) or D- (for low speed) ~1.5k ohm
pull up resistor, and then turns it back on very quickly, common hosts will sometimes
reject this event, since no human could ever unplug and reattach a USB device in a
microseconds (or nanoseconds) timescale. The host could simply treat this as some kind
of glitch and ignore the event altogether.
Parameters:
None
Return Values:
None
Remarks:
See also the USBDeviceDetach() API function documentation.
****************************************************************************/
#if defined(USB_INTERRUPT)
void USBDeviceAttach(void)
{
//if we are in the detached state
if(USBDeviceState == DETACHED_STATE)
{
if(USB_BUS_SENSE == 1)
{
//Initialize registers to known states.
U1CON = 0;
// Mask all USB interrupts
U1IE = 0;
//Configure things like: pull ups, full/low-speed mode,
//set the ping pong mode, and set internal transceiver
SetConfigurationOptions();
USBEnableInterrupts(); //Modifies global interrupt settings
// Enable module & attach to bus
while(!U1CONbits.USBEN){U1CONbits.USBEN = 1;}
//moved to the attached state
USBDeviceState = ATTACHED_STATE;
#ifdef USB_SUPPORT_OTG
U1OTGCON = USB_OTG_DPLUS_ENABLE | USB_OTG_ENABLE;
#endif
}
}
}
#endif //#if defined(USB_INTERRUPT)
/*******************************************************************************
Function: void USBCtrlEPAllowStatusStage(void);
Summary: This function prepares the proper endpoint 0 IN or endpoint 0 OUT
(based on the controlTransferState) to allow the status stage packet
of a control transfer to complete. This function gets used
internally by the USB stack itself, but it may also be called from
the application firmware, IF the application firmware called
the USBDeferStatusStage() function during the initial processing
of the control transfer request. In this case, the application
must call the USBCtrlEPAllowStatusStage() once, after it has fully
completed processing and handling the data stage portion of the
request.
If the application firmware has no need for delaying control
transfers, and therefore never calls USBDeferStatusStage(), then the
application firmware should not call USBCtrlEPAllowStatusStage().
Description:
Conditions:
None
Input:
Return:
Remarks:
None
*****************************************************************************/
void USBCtrlEPAllowStatusStage(void)
{
//Check and set two flags, prior to actually modifying any BDT entries.
//This double checking is necessary to make certain that
//USBCtrlEPAllowStatusStage() can be called twice simultaneously (ex: once
//in main loop context, while simultaneously getting an interrupt which
//tries to call USBCtrlEPAllowStatusStage() again, at the same time).
if(USBStatusStageEnabledFlag1 == FALSE)
{
USBStatusStageEnabledFlag1 = TRUE;
if(USBStatusStageEnabledFlag2 == FALSE)
{
USBStatusStageEnabledFlag2 = TRUE;
//Determine which endpoints (EP0 IN or OUT needs arming for the status
//stage), based on the type of control transfer currently pending.
if(controlTransferState == CTRL_TRF_RX)
{
pBDTEntryIn[0]->CNT = 0;
pBDTEntryIn[0]->STAT.Val = _USIE|_DAT1|(_DTSEN & _DTS_CHECKING_ENABLED);
}
else if(controlTransferState == CTRL_TRF_TX)
{
BothEP0OutUOWNsSet = FALSE; //Indicator flag used in USBCtrlTrfOutHandler()
//This buffer (when ping pong buffering is enabled on EP0 OUT) receives the
//next SETUP packet.
#if((USB_PING_PONG_MODE == USB_PING_PONG__EP0_OUT_ONLY) || (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG))
pBDTEntryEP0OutCurrent->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutCurrent->ADR = ConvertToPhysicalAddress(&SetupPkt);
pBDTEntryEP0OutCurrent->STAT.Val = _USIE|_BSTALL; //Prepare endpoint to accept a SETUP transaction
BothEP0OutUOWNsSet = TRUE; //Indicator flag used in USBCtrlTrfOutHandler()
#endif
//This EP0 OUT buffer receives the 0-byte OUT status stage packet.
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&SetupPkt);
pBDTEntryEP0OutNext->STAT.Val = _USIE; // Note: DTSEN is 0
}
}
}
}
/*******************************************************************************
Function: void USBCtrlEPAllowDataStage(void);
Summary: This function allows the data stage of either a host-to-device or
device-to-host control transfer (with data stage) to complete.
This function is meant to be used in conjunction with either the
USBDeferOUTDataStage() or USBDeferINDataStage(). If the firmware
does not call either USBDeferOUTDataStage() or USBDeferINDataStage(),
then the firmware does not need to manually call
USBCtrlEPAllowDataStage(), as the USB stack will call this function
instead.
Description:
Conditions: A control transfer (with data stage) should already be pending,
if the firmware calls this function. Additionally, the firmware
should have called either USBDeferOUTDataStage() or
USBDeferINDataStage() at the start of the control transfer, if
the firmware will be calling this function manually.
Input:
Return:
Remarks:
*****************************************************************************/
void USBCtrlEPAllowDataStage(void)
{
USBDeferINDataStagePackets = FALSE;
USBDeferOUTDataStagePackets = FALSE;
if(controlTransferState == CTRL_TRF_RX) //(<setup><out><out>...<out><in>)
{
//Prepare EP0 OUT to receive the first OUT data packet in the data stage sequence.
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&CtrlTrfData);
pBDTEntryEP0OutNext->STAT.Val = _USIE|_DAT1|(_DTSEN & _DTS_CHECKING_ENABLED);
}
else //else must be controlTransferState == CTRL_TRF_TX (<setup><in><in>...<in><out>)
{
//Error check the data stage byte count. Make sure the user specified
//value was no greater than the number of bytes the host requested.
if(SetupPkt.wLength < inPipes[0].wCount.Val)
{
inPipes[0].wCount.Val = SetupPkt.wLength;
}
USBCtrlTrfTxService(); //Copies one IN data packet worth of data from application buffer
//to CtrlTrfData buffer. Also keeps track of how many bytes remaining.
//Cnt should have been initialized by responsible request owner (ex: by
//using the USBEP0SendRAMPtr() or USBEP0SendROMPtr() API function).
pBDTEntryIn[0]->ADR = ConvertToPhysicalAddress(&CtrlTrfData);
pBDTEntryIn[0]->STAT.Val = _USIE|_DAT1|(_DTSEN & _DTS_CHECKING_ENABLED);
}
}
/******************************************************************************/
/** Internal Functions *********************************************************/
/******************************************************************************/
/********************************************************************
* Function: void USBConfigureEndpoint(BYTE EPNum, BYTE direction)
*
* PreCondition: None
*
* Input: BYTE EPNum - the endpoint to be configured
* BYTE direction - the direction to be configured
* (either OUT_FROM_HOST or IN_TO_HOST)
*
* Output: None
*
* Side Effects: None
*
* Overview: This function will configure the specified
* endpoint
*
* Note: None
*******************************************************************/
static void USBConfigureEndpoint(BYTE EPNum, BYTE direction)
{
volatile BDT_ENTRY* handle;
//Compute a pointer to the even BDT entry corresponding to the
//EPNum and direction values passed to this function.
handle = (volatile BDT_ENTRY*)&BDT[EP0_OUT_EVEN]; //Get address of start of BDT
handle += EP(EPNum,direction,0u); //Add in offset to the BDT of interest
handle->STAT.UOWN = 0; //mostly redundant, since USBStdSetCfgHandler()
//already cleared the entire BDT table
//Make sure our pBDTEntryIn/Out[] pointer is initialized. Needed later
//for USBTransferOnePacket() API calls.
if(direction == OUT_FROM_HOST)
{
pBDTEntryOut[EPNum] = handle;
}
else
{
pBDTEntryIn[EPNum] = handle;
}
#if (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG)
handle->STAT.DTS = 0;
(handle+1)->STAT.DTS = 1;
#elif (USB_PING_PONG_MODE == USB_PING_PONG__NO_PING_PONG)
//Set DTS to one because the first thing we will do
//when transmitting is toggle the bit
handle->STAT.DTS = 1;
#elif (USB_PING_PONG_MODE == USB_PING_PONG__EP0_OUT_ONLY)
if(EPNum != 0)
{
handle->STAT.DTS = 1;
}
#elif (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0)
if(EPNum != 0)
{
handle->STAT.DTS = 0;
(handle+1)->STAT.DTS = 1;
}
#endif
}
/******************************************************************************
* Function: void USBCtrlEPServiceComplete(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine wrap up the remaining tasks in servicing
* a Setup Request. Its main task is to set the endpoint
* controls appropriately for a given situation. See code
* below.
* There are three main scenarios:
* a) There was no handler for the Request, in this case
* a STALL should be sent out.
* b) The host has requested a read control transfer,
* endpoints are required to be setup in a specific way.
* c) The host has requested a write control transfer, or
* a control data stage is not required, endpoints are
* required to be setup in a specific way.
*
* Packet processing is resumed by clearing PKTDIS bit.
*
* Note: None
*****************************************************************************/
static void USBCtrlEPServiceComplete(void)
{
/*
* PKTDIS bit is set when a Setup Transaction is received.
* Clear to resume packet processing.
*/
USBPacketDisable = 0;
//Check the busy bits and the SetupPtk.DataDir variables to determine what type of
//control transfer is currently in progress. We need to know the type of control
//transfer that is currently pending, in order to know how to properly arm the
//EP0 IN and EP0 OUT endpoints.
if(inPipes[0].info.bits.busy == 0)
{
if(outPipes[0].info.bits.busy == 1)
{
controlTransferState = CTRL_TRF_RX;
/*
* Control Write:
* <SETUP[0]><OUT[1]><OUT[0]>...<IN[1]> | <SETUP[0]>
*/
//1. Prepare OUT EP to receive data, unless a USB class request handler
// function decided to defer the data stage (ex: because the intended
// RAM buffer wasn't available yet) by calling USBDeferDataStage().
// If it did so, it is then responsible for calling USBCtrlEPAllowDataStage(),
// once it is ready to begin receiving the data.
if(USBDeferOUTDataStagePackets == FALSE)
{
USBCtrlEPAllowDataStage();
}
//2. IN endpoint 0 status stage will be armed by USBCtrlEPAllowStatusStage()
//after all of the OUT data has been received and consumed, or if a timeout occurs.
USBStatusStageEnabledFlag2 = FALSE;
USBStatusStageEnabledFlag1 = FALSE;
}
else
{
/*
* If no one knows how to service this request then stall.
* Must also prepare EP0 to receive the next SETUP transaction.
*/
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&SetupPkt);
pBDTEntryEP0OutNext->STAT.Val = _USIE|_DAT0|(_DTSEN & _DTS_CHECKING_ENABLED)|_BSTALL;
pBDTEntryIn[0]->STAT.Val = _USIE|_BSTALL;
}
}
else // A module has claimed ownership of the control transfer session.
{
if(SetupPkt.DataDir == USB_SETUP_DEVICE_TO_HOST_BITFIELD)
{
controlTransferState = CTRL_TRF_TX;
/*
* Control Read:
* <SETUP[0]><IN[1]><IN[0]>...<OUT[1]> | <SETUP[0]>
*
* 1. Prepare IN EP to transfer data to the host. If however the data
* wasn't ready yet (ex: because the firmware needs to go and read it from
* some slow/currently unavailable resource, such as an external I2C EEPROM),
* Then the class request handler reponsible should call the USBDeferDataStage()
* macro. In this case, the firmware may wait up to 500ms, before it is required
* to transmit the first IN data packet. Once the data is ready, and the firmware
* is ready to begin sending the data, it should then call the
* USBCtrlEPAllowDataStage() function to start the data stage.
*/
if(USBDeferINDataStagePackets == FALSE)
{
USBCtrlEPAllowDataStage();
}
// 2. (Optionally) allow the status stage now, to prepare for early termination.
// Note: If a class request handler decided to set USBDeferStatusStagePacket == TRUE,
// then it is responsible for eventually calling USBCtrlEPAllowStatusStage() once it
// is ready. If the class request handler does this, it needs to be careful to
// be written so that it can handle the early termination scenario.
// Ex: It should call USBCtrlEPAllowStatusStage() when any of the following occurs:
// 1. The desired total number of bytes were sent to the host.
// 2. The number of bytes that the host originally requested (in the SETUP packet that
// started the control transfer) has been reached.
// 3. Or, if a timeout occurs (ex: <50ms since the last successful EP0 IN transaction), regardless
// of how many bytes have actually been sent. This is necessary to prevent a deadlock situation
// (where the control transfer can't complete, due to continuous NAK on status stage) if the
// host performs early termination. If enabled, the USB_ENABLE_STATUS_STAGE_TIMEOUTS usb_config.h
// option can take care of this for you.
// Note: For this type of control transfer, there is normally no harm in simply arming the
// status stage packet right now, even if the IN data is not ready yet. This allows for
// immediate early termination, without adding unecessary delay. Therefore, it is generally not
// recommended for the USB class handler firmware to call USBDeferStatusStage(), for this
// type of control transfer. If the USB class handler firmware needs more time to fetch the IN
// data that needs to be sent to the host, it should instead use the USBDeferDataStage() function.
USBStatusStageEnabledFlag2 = FALSE;
USBStatusStageEnabledFlag1 = FALSE;
if(USBDeferStatusStagePacket == FALSE)
{
USBCtrlEPAllowStatusStage();
}
}
else // (SetupPkt.DataDir == USB_SETUP_DIRECTION_HOST_TO_DEVICE)
{
//This situation occurs for special types of control transfers,
//such as that which occurs when the host sends a SET_ADDRESS
//control transfer. Ex:
//
//<SETUP[0]><IN[1]> | <SETUP[0]>
//Although the data direction is HOST_TO_DEVICE, there is no data stage
//(hence: outPipes[0].info.bits.busy == 0). There is however still
//an IN status stage.
controlTransferState = CTRL_TRF_RX; //Since this is a HOST_TO_DEVICE control transfer
//1. Prepare OUT EP to receive the next SETUP packet.
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&SetupPkt);
pBDTEntryEP0OutNext->STAT.Val = _USIE|_BSTALL;
//2. Prepare for IN status stage of the control transfer
USBStatusStageEnabledFlag2 = FALSE;
USBStatusStageEnabledFlag1 = FALSE;
if(USBDeferStatusStagePacket == FALSE)
{
USBCtrlEPAllowStatusStage();
}
}
}//end if(ctrl_trf_session_owner == MUID_NULL)
}//end USBCtrlEPServiceComplete
/******************************************************************************
* Function: void USBCtrlTrfTxService(void)
*
* PreCondition: pSrc, wCount, and usb_stat.ctrl_trf_mem are setup properly.
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine is used for device to host control transfers
* (IN transactions). This function takes care of managing a
* transfer over multiple USB transactions.
* This routine should be called from only two places.
* One from USBCtrlEPServiceComplete() and one from
* USBCtrlTrfInHandler().
*
* Note:
*****************************************************************************/
static void USBCtrlTrfTxService(void)
{
BYTE byteToSend;
//Figure out how many bytes of data to send in the next IN transaction.
//Assume a full size packet, unless otherwise determined below.
byteToSend = USB_EP0_BUFF_SIZE;
if(inPipes[0].wCount.Val < (BYTE)USB_EP0_BUFF_SIZE)
{
byteToSend = inPipes[0].wCount.Val;
//Keep track of whether or not we have sent a "short packet" yet.
//This is useful so that later on, we can configure EP0 IN to STALL,
//after we have sent all of the intended data. This makes sure the
//hardware STALLs if the host erroneously tries to send more IN token
//packets, requesting more data than intended in the control transfer.
if(shortPacketStatus == SHORT_PKT_NOT_USED)
{
shortPacketStatus = SHORT_PKT_PENDING;
}
else if(shortPacketStatus == SHORT_PKT_PENDING)
{
shortPacketStatus = SHORT_PKT_SENT;
}
}
//Keep track of how many bytes remain to be sent in the transfer, by
//subtracting the number of bytes about to be sent from the total.
inPipes[0].wCount.Val = inPipes[0].wCount.Val - byteToSend;
//Next, load the number of bytes to send to BC7..0 in buffer descriptor.
//Note: Control endpoints may never have a max packet size of > 64 bytes.
//Therefore, the BC8 and BC9 bits should always be maintained clear.
pBDTEntryIn[0]->CNT = byteToSend;
//Now copy the data from the source location, to the CtrlTrfData[] buffer,
//which we will send to the host.
pDst = (USB_VOLATILE BYTE*)CtrlTrfData; // Set destination pointer
if(inPipes[0].info.bits.ctrl_trf_mem == USB_EP0_ROM) // Determine type of memory source
{
while(byteToSend)
{
*pDst++ = *inPipes[0].pSrc.bRom++;
byteToSend--;
}//end while(byte_to_send.Val)
}
else // RAM
{
while(byteToSend)
{
*pDst++ = *inPipes[0].pSrc.bRam++;
byteToSend--;
}//end while(byte_to_send.Val)
}//end if(usb_stat.ctrl_trf_mem == _ROM)
}//end USBCtrlTrfTxService
/******************************************************************************
* Function: void USBCtrlTrfRxService(void)
*
* PreCondition: pDst and wCount are setup properly.
* pSrc is always &CtrlTrfData
* usb_stat.ctrl_trf_mem is always USB_EP0_RAM.
* wCount should be set to 0 at the start of each control
* transfer.
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine is used for host to device control transfers
* (uses OUT transactions). This function receives the data that arrives
* on EP0 OUT, and copies it into the appropriate outPipes[0].pDst.bRam
* buffer. Once the host has sent all the data it was intending
* to send, this function will call the appropriate outPipes[0].pFunc()
* handler (unless it is NULL), so that it can be used by the
* intended target firmware.
*
* Note: None
*****************************************************************************/
static void USBCtrlTrfRxService(void)
{
BYTE byteToRead;
BYTE i;
//Load byteToRead with the number of bytes the host just sent us in the
//last OUT transaction.
byteToRead = pBDTEntryEP0OutCurrent->CNT;
//Update the "outPipes[0].wCount.Val", which keeps track of the total number
//of remaining bytes expected to be received from the host, in the control
//transfer. First check to see if the host sent us more bytes than the
//application firmware was expecting to receive.
if(byteToRead > outPipes[0].wCount.Val)
{
byteToRead = outPipes[0].wCount.Val;
}
//Reduce the number of remaining bytes by the number we just received.
outPipes[0].wCount.Val = outPipes[0].wCount.Val - byteToRead;
//Copy the OUT DATAx packet bytes that we just received from the host,
//into the user application buffer space.
for(i=0;i<byteToRead;i++)
{
*outPipes[0].pDst.bRam++ = CtrlTrfData[i];
}//end while(byteToRead.Val)
//If there is more data to receive, prepare EP0 OUT so that it can receive
//the next packet in the sequence.
if(outPipes[0].wCount.Val > 0)
{
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&CtrlTrfData);
if(pBDTEntryEP0OutCurrent->STAT.DTS == 0)
{
pBDTEntryEP0OutNext->STAT.Val = _USIE|_DAT1|(_DTSEN & _DTS_CHECKING_ENABLED);
}
else
{
pBDTEntryEP0OutNext->STAT.Val = _USIE|_DAT0|(_DTSEN & _DTS_CHECKING_ENABLED);
}
}
else
{
//We have received all OUT packets that we were expecting to
//receive for the control transfer. Prepare EP0 OUT to receive
//the next SETUP transaction that may arrive.
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&SetupPkt);
//Configure EP0 OUT to receive the next SETUP transaction for any future
//control transfers. However, set BSTALL in case the host tries to send
//more data than it claims it was going to send.
pBDTEntryEP0OutNext->STAT.Val = _USIE|_BSTALL;
//All data bytes for the host to device control write (OUT) have now been
//received successfully.
//Go ahead and call the user specified callback function, to use/consume
//the control transfer data (ex: if the "void (*function)" parameter
//was non-NULL when USBEP0Receive() was called).
if(outPipes[0].pFunc != NULL)
{
#if defined(__XC8)
//Special pragmas to suppress an expected/harmless warning
//message when building with the XC8 compiler
#pragma warning push
#pragma warning disable 1088
outPipes[0].pFunc(); //Call the user's callback function
#pragma warning pop
#else
outPipes[0].pFunc(); //Call the user's callback function
#endif
}
outPipes[0].info.bits.busy = 0;
//Ready to arm status stage IN transaction now, if the application
//firmware has completed processing the request. If it is still busy
//and needs more time to finish handling the request, then the user
//callback (the one called by the outPipes[0].pFunc();) should set the
//USBDeferStatusStagePacket to TRUE (by calling USBDeferStatusStage()). In
//this case, it is the application's firmware responsibility to call
//the USBCtrlEPAllowStatusStage() function, once it is fully done handling the request.
//Note: The application firmware must process the request and call
//USBCtrlEPAllowStatusStage() in a semi-timely fashion. "Semi-timely"
//means either 50ms, 500ms, or 5 seconds, depending on the type of
//control transfer. See the USB 2.0 specification section 9.2.6 for
//more details.
if(USBDeferStatusStagePacket == FALSE)
{
USBCtrlEPAllowStatusStage();
}
}
}//end USBCtrlTrfRxService
/********************************************************************
* Function: void USBStdSetCfgHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine first disables all endpoints by
* clearing UEP registers. It then configures
* (initializes) endpoints by calling the callback
* function USBCBInitEP().
*
* Note: None
*******************************************************************/
static void USBStdSetCfgHandler(void)
{
BYTE i;
// This will generate a zero length packet
inPipes[0].info.bits.busy = 1;
//Clear all of the endpoint control registers
DisableNonZeroEndpoints(USB_MAX_EP_NUMBER);
//Clear all of the BDT entries
memset((void*)&BDT[0], 0x00, sizeof(BDT));
// Assert reset request to all of the Ping Pong buffer pointers
USBPingPongBufferReset = 1;
//Re-Initialize all ping pong software state bits to 0 (which corresponds to
//the EVEN buffer being the next one that will be used), since we are also
//doing a hardware ping pong pointer reset above.
for(i = 0; i < (BYTE)(USB_MAX_EP_NUMBER+1u); i++)
{
ep_data_in[i].Val = 0u;
ep_data_out[i].Val = 0u;
}
//clear the alternate interface settings
memset((void*)&USBAlternateInterface,0x00,USB_MAX_NUM_INT);
//Stop trying to reset ping pong buffer pointers
USBPingPongBufferReset = 0;
pBDTEntryIn[0] = (volatile BDT_ENTRY*)&BDT[EP0_IN_EVEN];
//Set the next out to the current out packet
pBDTEntryEP0OutCurrent = (volatile BDT_ENTRY*)&BDT[EP0_OUT_EVEN];
pBDTEntryEP0OutNext = pBDTEntryEP0OutCurrent;
//set the current configuration
USBActiveConfiguration = SetupPkt.bConfigurationValue;
//if the configuration value == 0
if(USBActiveConfiguration == 0)
{
//Go back to the addressed state
USBDeviceState = ADDRESS_STATE;
}
else
{
//initialize the required endpoints
USB_SET_CONFIGURATION_HANDLER(EVENT_CONFIGURED,(void*)&USBActiveConfiguration,1);
//Otherwise go to the configured state. Update the state variable last,
//after performing all of the set configuration related initialization
//tasks.
USBDeviceState = CONFIGURED_STATE;
}//end if(SetupPkt.bConfigurationValue == 0)
}//end USBStdSetCfgHandler
/********************************************************************
* Function: void USBStdGetDscHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine handles the standard GET_DESCRIPTOR
* request.
*
* Note: None
*******************************************************************/
static void USBStdGetDscHandler(void)
{
if(SetupPkt.bmRequestType == 0x80)
{
inPipes[0].info.Val = USB_EP0_ROM | USB_EP0_BUSY | USB_EP0_INCLUDE_ZERO;
switch(SetupPkt.bDescriptorType)
{
case USB_DESCRIPTOR_DEVICE:
#if !defined(USB_USER_DEVICE_DESCRIPTOR)
inPipes[0].pSrc.bRom = (ROM BYTE*)&device_dsc;
#else
inPipes[0].pSrc.bRom = (ROM BYTE*)USB_USER_DEVICE_DESCRIPTOR;
#endif
inPipes[0].wCount.Val = sizeof(device_dsc);
break;
case USB_DESCRIPTOR_CONFIGURATION:
#if !defined(USB_USER_CONFIG_DESCRIPTOR)
inPipes[0].pSrc.bRom = *(USB_CD_Ptr+SetupPkt.bDscIndex);
#else
inPipes[0].pSrc.bRom = *(USB_USER_CONFIG_DESCRIPTOR+SetupPkt.bDscIndex);
#endif
//This must be loaded using byte addressing. The source pointer
// may not be word aligned for the 16 or 32 bit machines resulting
// in an address error on the dereference.
inPipes[0].wCount.byte.LB = *(inPipes[0].pSrc.bRom+2);
inPipes[0].wCount.byte.HB = *(inPipes[0].pSrc.bRom+3);
break;
case USB_DESCRIPTOR_STRING:
//USB_NUM_STRING_DESCRIPTORS was introduced as optional in release v2.3. In v2.4 and
// later it is now manditory. This should be defined in usb_config.h and should
// indicate the number of string descriptors.
if(SetupPkt.bDscIndex<USB_NUM_STRING_DESCRIPTORS)
{
//Get a pointer to the String descriptor requested
inPipes[0].pSrc.bRom = *(USB_SD_Ptr+SetupPkt.bDscIndex);
// Set data count
inPipes[0].wCount.Val = *inPipes[0].pSrc.bRom;
}
#if defined(IMPLEMENT_MICROSOFT_OS_DESCRIPTOR)
else if(SetupPkt.bDscIndex == MICROSOFT_OS_DESCRIPTOR_INDEX)
{
//Get a pointer to the special MS OS string descriptor requested
inPipes[0].pSrc.bRom = (ROM BYTE*)&MSOSDescriptor;
// Set data count
inPipes[0].wCount.Val = *inPipes[0].pSrc.bRom;
}
#endif
else
{
inPipes[0].info.Val = 0;
}
break;
default:
inPipes[0].info.Val = 0;
break;
}//end switch
}//end if
}//end USBStdGetDscHandler
/********************************************************************
* Function: void USBStdGetStatusHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine handles the standard GET_STATUS request
*
* Note: None
*******************************************************************/
static void USBStdGetStatusHandler(void)
{
CtrlTrfData[0] = 0; // Initialize content
CtrlTrfData[1] = 0;
switch(SetupPkt.Recipient)
{
case USB_SETUP_RECIPIENT_DEVICE_BITFIELD:
inPipes[0].info.bits.busy = 1;
/*
* [0]: bit0: Self-Powered Status [0] Bus-Powered [1] Self-Powered
* bit1: RemoteWakeup [0] Disabled [1] Enabled
*/
if(self_power == 1) // self_power is defined in HardwareProfile.h
{
CtrlTrfData[0]|=0x01;
}
if(RemoteWakeup == TRUE)
{
CtrlTrfData[0]|=0x02;
}
break;
case USB_SETUP_RECIPIENT_INTERFACE_BITFIELD:
inPipes[0].info.bits.busy = 1; // No data to update
break;
case USB_SETUP_RECIPIENT_ENDPOINT_BITFIELD:
inPipes[0].info.bits.busy = 1;
/*
* [0]: bit0: Halt Status [0] Not Halted [1] Halted
*/
{
BDT_ENTRY *p;
if(SetupPkt.EPDir == 0)
{
p = (BDT_ENTRY*)pBDTEntryOut[SetupPkt.EPNum];
}
else
{
p = (BDT_ENTRY*)pBDTEntryIn[SetupPkt.EPNum];
}
if((p->STAT.UOWN == 1) && (p->STAT.BSTALL == 1))
CtrlTrfData[0]=0x01; // Set bit0
break;
}
}//end switch
if(inPipes[0].info.bits.busy == 1)
{
inPipes[0].pSrc.bRam = (BYTE*)&CtrlTrfData; // Set Source
inPipes[0].info.bits.ctrl_trf_mem = USB_EP0_RAM; // Set memory type
inPipes[0].wCount.v[0] = 2; // Set data count
}//end if(...)
}//end USBStdGetStatusHandler
/********************************************************************
* Function: void USBStallHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects:
*
* Overview: This function handles the event of a STALL
* occuring on the bus
*
* Note: None
*******************************************************************/
static void USBStallHandler(void)
{
/*
* Does not really have to do anything here,
* even for the control endpoint.
* All BDs of Endpoint 0 are owned by SIE right now,
* but once a Setup Transaction is received, the ownership
* for EP0_OUT will be returned to CPU.
* When the Setup Transaction is serviced, the ownership
* for EP0_IN will then be forced back to CPU by firmware.
*/
/* v2b fix */
if(U1EP0bits.EPSTALL == 1)
{
// UOWN - if 0, owned by CPU, if 1, owned by SIE
if((pBDTEntryEP0OutCurrent->STAT.Val == _USIE) && (pBDTEntryIn[0]->STAT.Val == (_USIE|_BSTALL)))
{
// Set ep0Bo to stall also
pBDTEntryEP0OutCurrent->STAT.Val = _USIE|_DAT0|(_DTSEN & _DTS_CHECKING_ENABLED)|_BSTALL;
}//end if
U1EP0bits.EPSTALL = 0; // Clear stall status
}//end if
USBClearInterruptFlag(USBStallIFReg,USBStallIFBitNum);
}
/********************************************************************
* Function: void USBSuspend(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects:
*
* Overview: This function handles if the host tries to
* suspend the device
*
* Note: None
*******************************************************************/
static void USBSuspend(void)
{
/*
* NOTE: Do not clear UIRbits.ACTVIF here!
* Reason:
* ACTVIF is only generated once an IDLEIF has been generated.
* This is a 1:1 ratio interrupt generation.
* For every IDLEIF, there will be only one ACTVIF regardless of
* the number of subsequent bus transitions.
*
* If the ACTIF is cleared here, a problem could occur when:
* [ IDLE ][bus activity ->
* <--- 3 ms -----> ^
* ^ ACTVIF=1
* IDLEIF=1
* # # # # (#=Program polling flags)
* ^
* This polling loop will see both
* IDLEIF=1 and ACTVIF=1.
* However, the program services IDLEIF first
* because ACTIVIE=0.
* If this routine clears the only ACTIVIF,
* then it can never get out of the suspend
* mode.
*/
USBActivityIE = 1; // Enable bus activity interrupt
USBClearInterruptFlag(USBIdleIFReg,USBIdleIFBitNum);
#if defined(__18CXX) || defined(_PIC14E)
U1CONbits.SUSPND = 1; // Put USB module in power conserve
// mode, SIE clock inactive
#endif
USBBusIsSuspended = TRUE;
/*
* At this point the PIC can go into sleep,idle, or
* switch to a slower clock, etc. This should be done in the
* USBCBSuspend() if necessary.
*/
USB_SUSPEND_HANDLER(EVENT_SUSPEND,0,0);
}
/********************************************************************
* Function: void USBWakeFromSuspend(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview:
*
* Note: None
*******************************************************************/
static void USBWakeFromSuspend(void)
{
USBBusIsSuspended = FALSE;
/*
* If using clock switching, the place to restore the original
* microcontroller core clock frequency is in the USBCBWakeFromSuspend() callback
*/
USB_WAKEUP_FROM_SUSPEND_HANDLER(EVENT_RESUME,0,0);
#if defined(__18CXX) || defined(_PIC14E)
//To avoid improperly clocking the USB module, make sure the oscillator
//settings are consistant with USB operation before clearing the SUSPND bit.
//Make sure the correct oscillator settings are selected in the
//"USB_WAKEUP_FROM_SUSPEND_HANDLER(EVENT_RESUME,0,0)" handler.
U1CONbits.SUSPND = 0; // Bring USB module out of power conserve
// mode.
#endif
USBActivityIE = 0;
/********************************************************************
Bug Fix: Feb 26, 2007 v2.1
*********************************************************************
The ACTVIF bit cannot be cleared immediately after the USB module wakes
up from Suspend or while the USB module is suspended. A few clock cycles
are required to synchronize the internal hardware state machine before
the ACTIVIF bit can be cleared by firmware. Clearing the ACTVIF bit
before the internal hardware is synchronized may not have an effect on
the value of ACTVIF. Additonally, if the USB module uses the clock from
the 96 MHz PLL source, then after clearing the SUSPND bit, the USB
module may not be immediately operational while waiting for the 96 MHz
PLL to lock.
********************************************************************/
// UIRbits.ACTVIF = 0; // Removed
#if defined(__18CXX)
while(USBActivityIF)
#endif
{
USBClearInterruptFlag(USBActivityIFReg,USBActivityIFBitNum);
} // Added
}//end USBWakeFromSuspend
/********************************************************************
* Function: void USBCtrlEPService(void)
*
* PreCondition: USTAT is loaded with a valid endpoint address.
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: USBCtrlEPService checks for three transaction
* types that it knows how to service and services
* them:
* 1. EP0 SETUP
* 2. EP0 OUT
* 3. EP0 IN
* It ignores all other types (i.e. EP1, EP2, etc.)
*
* Note: None
*******************************************************************/
static void USBCtrlEPService(void)
{
//If we get to here, that means a successful transaction has just occurred
//on EP0. This means "progress" has occurred in the currently pending
//control transfer, so we should re-initialize our timeout counter.
#if defined(USB_ENABLE_STATUS_STAGE_TIMEOUTS)
USBStatusStageTimeoutCounter = USB_STATUS_STAGE_TIMEOUT;
#endif
//Check if the last transaction was on EP0 OUT endpoint (of any kind, to either the even or odd buffer if ping pong buffers used)
if((USTATcopy.Val & USTAT_EP0_PP_MASK) == USTAT_EP0_OUT_EVEN)
{
//Point to the EP0 OUT buffer of the buffer that arrived
#if defined (_PIC14E) || defined(__18CXX)
pBDTEntryEP0OutCurrent = (volatile BDT_ENTRY*)&BDT[(USTATcopy.Val & USTAT_EP_MASK)>>1];
#elif defined(__C30__) || defined(__C32__) || defined __XC16__
pBDTEntryEP0OutCurrent = (volatile BDT_ENTRY*)&BDT[(USTATcopy.Val & USTAT_EP_MASK)>>2];
#else
#error "unimplemented"
#endif
//Set the next out to the current out packet
pBDTEntryEP0OutNext = pBDTEntryEP0OutCurrent;
//Toggle it to the next ping pong buffer (if applicable)
((BYTE_VAL*)&pBDTEntryEP0OutNext)->Val ^= USB_NEXT_EP0_OUT_PING_PONG;
//If the current EP0 OUT buffer has a SETUP packet
if(pBDTEntryEP0OutCurrent->STAT.PID == PID_SETUP)
{
unsigned char setup_cnt;
//The SETUP transaction data may have gone into the the CtrlTrfData
//buffer, or elsewhere, depending upon how the BDT was prepared
//before the transaction. Therefore, we should copy the data to the
//SetupPkt buffer so it can be processed correctly by USBCtrlTrfSetupHandler().
for(setup_cnt = 0; setup_cnt < 8u; setup_cnt++) //SETUP data packets always contain exactly 8 bytes.
{
*(BYTE*)((BYTE*)&SetupPkt + setup_cnt) = *(BYTE*)ConvertToVirtualAddress(pBDTEntryEP0OutCurrent->ADR);
pBDTEntryEP0OutCurrent->ADR++;
}
pBDTEntryEP0OutCurrent->ADR = ConvertToPhysicalAddress(&SetupPkt);
//Handle the control transfer (parse the 8-byte SETUP command and figure out what to do)
USBCtrlTrfSetupHandler();
}
else
{
//Handle the DATA transfer
USBCtrlTrfOutHandler();
}
}
else if((USTATcopy.Val & USTAT_EP0_PP_MASK) == USTAT_EP0_IN)
{
//Otherwise the transmission was and EP0 IN
// so take care of the IN transfer
USBCtrlTrfInHandler();
}
}//end USBCtrlEPService
/********************************************************************
* Function: void USBCtrlTrfSetupHandler(void)
*
* PreCondition: SetupPkt buffer is loaded with valid USB Setup Data
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine is a task dispatcher and has 3 stages.
* 1. It initializes the control transfer state machine.
* 2. It calls on each of the module that may know how to
* service the Setup Request from the host.
* Module Example: USBD, HID, CDC, MSD, ...
* A callback function, USBCBCheckOtherReq(),
* is required to call other module handlers.
* 3. Once each of the modules has had a chance to check if
* it is responsible for servicing the request, stage 3
* then checks direction of the transfer to determine how
* to prepare EP0 for the control transfer.
* Refer to USBCtrlEPServiceComplete() for more details.
*
* Note: Microchip USB Firmware has three different states for
* the control transfer state machine:
* 1. WAIT_SETUP
* 2. CTRL_TRF_TX (device sends data to host through IN transactions)
* 3. CTRL_TRF_RX (device receives data from host through OUT transactions)
* Refer to firmware manual to find out how one state
* is transitioned to another.
*
* A Control Transfer is composed of many USB transactions.
* When transferring data over multiple transactions,
* it is important to keep track of data source, data
* destination, and data count. These three parameters are
* stored in pSrc,pDst, and wCount. A flag is used to
* note if the data source is from ROM or RAM.
*
*******************************************************************/
static void USBCtrlTrfSetupHandler(void)
{
//--------------------------------------------------------------------------
//1. Re-initialize state tracking variables related to control transfers.
//--------------------------------------------------------------------------
shortPacketStatus = SHORT_PKT_NOT_USED;
USBDeferStatusStagePacket = FALSE;
USBDeferINDataStagePackets = FALSE;
USBDeferOUTDataStagePackets = FALSE;
BothEP0OutUOWNsSet = FALSE;
controlTransferState = WAIT_SETUP;
//Abandon any previous control transfers that might have been using EP0.
//Ordinarily, nothing actually needs abandoning, since the previous control
//transfer would have completed successfully prior to the host sending the next
//SETUP packet. However, in a timeout error case, or after an EP0 STALL event,
//one or more UOWN bits might still be set. If so, we should clear the UOWN bits,
//so the EP0 IN/OUT endpoints are in a known inactive state, ready for re-arming
//by the class request handler that will be called next.
pBDTEntryIn[0]->STAT.Val &= ~(_USIE);
((BYTE_VAL*)&pBDTEntryIn[0])->Val ^= USB_NEXT_EP0_IN_PING_PONG;
pBDTEntryIn[0]->STAT.Val &= ~(_USIE);
((BYTE_VAL*)&pBDTEntryIn[0])->Val ^= USB_NEXT_EP0_IN_PING_PONG;
pBDTEntryEP0OutNext->STAT.Val &= ~(_USIE);
inPipes[0].info.Val = 0;
inPipes[0].wCount.Val = 0;
outPipes[0].info.Val = 0;
outPipes[0].wCount.Val = 0;
//--------------------------------------------------------------------------
//2. Now find out what was in the SETUP packet, and begin handling the request.
//--------------------------------------------------------------------------
USBCheckStdRequest(); //Check for standard USB "Chapter 9" requests.
USB_NONSTANDARD_EP0_REQUEST_HANDLER(EVENT_EP0_REQUEST,0,0); //Check for USB device class specific requests
//--------------------------------------------------------------------------
//3. Re-arm EP0 IN and EP0 OUT endpoints, based on the control transfer in
// progress. If one of the above handlers (in step 2) knew how to process
// the request, it will have set one of the inPipes[0].info.bits.busy or
// outPipes[0].info.bits.busy flags = 1. This lets the
// USBCtrlEPServiceComplete() function know how and which endpoints to
// arm. If both info.bits.busy flags are = 0, then no one knew how to
// process the request. In this case, the default behavior will be to
// perform protocol STALL on EP0.
//--------------------------------------------------------------------------
USBCtrlEPServiceComplete();
}//end USBCtrlTrfSetupHandler
/******************************************************************************
* Function: void USBCtrlTrfOutHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine handles an OUT transaction according to
* which control transfer state is currently active.
*
* Note: Note that if the the control transfer was from
* host to device, the session owner should be notified
* at the end of each OUT transaction to service the
* received data.
*
*****************************************************************************/
static void USBCtrlTrfOutHandler(void)
{
if(controlTransferState == CTRL_TRF_RX)
{
USBCtrlTrfRxService(); //Copies the newly received data into the appropriate buffer and configures EP0 OUT for next transaction.
}
else //In this case the last OUT transaction must have been a status stage of a CTRL_TRF_TX (<setup><in><in>...<OUT> <-- this last OUT just occurred as the status stage)
{
//If the status stage is complete, this means we are done with the
//control transfer. Go back to the idle "WAIT_SETUP" state.
controlTransferState = WAIT_SETUP;
//Prepare EP0 OUT for the next SETUP transaction, however, it may have
//already been prepared if ping-pong buffering was enabled on EP0 OUT,
//and the last control transfer was of direction: device to host, see
//USBCtrlEPServiceComplete(). If it was already prepared, do not want
//to do anything to the BDT.
if(BothEP0OutUOWNsSet == FALSE)
{
pBDTEntryEP0OutNext->CNT = USB_EP0_BUFF_SIZE;
pBDTEntryEP0OutNext->ADR = ConvertToPhysicalAddress(&SetupPkt);
pBDTEntryEP0OutNext->STAT.Val = _USIE|_DAT0|(_DTSEN & _DTS_CHECKING_ENABLED)|_BSTALL;
}
else
{
BothEP0OutUOWNsSet = FALSE;
}
}
}
/******************************************************************************
* Function: void USBCtrlTrfInHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine handles an IN transaction according to
* which control transfer state is currently active.
*
* Note: A Set Address Request must not change the acutal address
* of the device until the completion of the control
* transfer. The end of the control transfer for Set Address
* Request is an IN transaction. Therefore it is necessary
* to service this unique situation when the condition is
* right. Macro mUSBCheckAdrPendingState is defined in
* usb9.h and its function is to specifically service this
* event.
*****************************************************************************/
static void USBCtrlTrfInHandler(void)
{
BYTE lastDTS;
lastDTS = pBDTEntryIn[0]->STAT.DTS;
//switch to the next ping pong buffer
((BYTE_VAL*)&pBDTEntryIn[0])->Val ^= USB_NEXT_EP0_IN_PING_PONG;
//Must check if in ADR_PENDING_STATE. If so, we need to update the address
//now, since the IN status stage of the (set address) control transfer has
//evidently completed successfully.
if(USBDeviceState == ADR_PENDING_STATE)
{
U1ADDR = SetupPkt.bDevADR.Val;
if(U1ADDR != 0u)
{
USBDeviceState=ADDRESS_STATE;
}
else
{
USBDeviceState=DEFAULT_STATE;
}
}//end if
if(controlTransferState == CTRL_TRF_TX)
{
pBDTEntryIn[0]->ADR = ConvertToPhysicalAddress(CtrlTrfData);
USBCtrlTrfTxService();
//Check if we have already sent a short packet. If so, configure
//the endpoint to STALL in response to any further IN tokens (in the
//case that the host erroneously tries to receive more data than it
//should).
if(shortPacketStatus == SHORT_PKT_SENT)
{
// If a short packet has been sent, don't want to send any more,
// stall next time if host is still trying to read.
pBDTEntryIn[0]->STAT.Val = _USIE|_BSTALL;
}
else
{
if(lastDTS == 0)
{
pBDTEntryIn[0]->STAT.Val = _USIE|_DAT1|(_DTSEN & _DTS_CHECKING_ENABLED);
}
else
{
pBDTEntryIn[0]->STAT.Val = _USIE|_DAT0|(_DTSEN & _DTS_CHECKING_ENABLED);
}
}//end if(...)else
}
else // must have been a CTRL_TRF_RX status stage IN packet (<setup><out><out>...<IN> <-- this last IN just occurred as the status stage)
{
//if someone is still expecting data from the control transfer
// then make sure to terminate that request and let them know that
// they are done
if(outPipes[0].info.bits.busy == 1)
{
if(outPipes[0].pFunc != NULL)
{
outPipes[0].pFunc();
}
outPipes[0].info.bits.busy = 0;
}
controlTransferState = WAIT_SETUP;
//Don't need to arm EP0 OUT here. It was already armed by the last <out> that
//got processed by the USBCtrlTrfRxService() handler.
}
}
/********************************************************************
* Function: void USBCheckStdRequest(void)
*
* PreCondition: None
*
* Input: None
*
* Output: None
*
* Side Effects: None
*
* Overview: This routine checks the setup data packet to see
* if it knows how to handle it
*
* Note: None
*******************************************************************/
static void USBCheckStdRequest(void)
{
if(SetupPkt.RequestType != USB_SETUP_TYPE_STANDARD_BITFIELD) return;
switch(SetupPkt.bRequest)
{
case USB_REQUEST_SET_ADDRESS:
inPipes[0].info.bits.busy = 1; // This will generate a zero length packet
USBDeviceState = ADR_PENDING_STATE; // Update state only
/* See USBCtrlTrfInHandler() for the next step */
break;
case USB_REQUEST_GET_DESCRIPTOR:
USBStdGetDscHandler();
break;
case USB_REQUEST_SET_CONFIGURATION:
USBStdSetCfgHandler();
break;
case USB_REQUEST_GET_CONFIGURATION:
inPipes[0].pSrc.bRam = (BYTE*)&USBActiveConfiguration; // Set Source
inPipes[0].info.bits.ctrl_trf_mem = USB_EP0_RAM; // Set memory type
inPipes[0].wCount.v[0] = 1; // Set data count
inPipes[0].info.bits.busy = 1;
break;
case USB_REQUEST_GET_STATUS:
USBStdGetStatusHandler();
break;
case USB_REQUEST_CLEAR_FEATURE:
case USB_REQUEST_SET_FEATURE:
USBStdFeatureReqHandler();
break;
case USB_REQUEST_GET_INTERFACE:
inPipes[0].pSrc.bRam = (BYTE*)&USBAlternateInterface[SetupPkt.bIntfID]; // Set source
inPipes[0].info.bits.ctrl_trf_mem = USB_EP0_RAM; // Set memory type
inPipes[0].wCount.v[0] = 1; // Set data count
inPipes[0].info.bits.busy = 1;
break;
case USB_REQUEST_SET_INTERFACE:
inPipes[0].info.bits.busy = 1;
USBAlternateInterface[SetupPkt.bIntfID] = SetupPkt.bAltID;
break;
case USB_REQUEST_SET_DESCRIPTOR:
USB_SET_DESCRIPTOR_HANDLER(EVENT_SET_DESCRIPTOR,0,0);
break;
case USB_REQUEST_SYNCH_FRAME:
default:
break;
}//end switch
}//end USBCheckStdRequest
/********************************************************************
* Function: void USBStdFeatureReqHandler(void)
*
* PreCondition: None
*
* Input: None
*
* Output: Can alter BDT entries. Can also modify USB stack
* Maintained variables.
*
* Side Effects: None
*
* Overview: This routine handles the standard SET & CLEAR
* FEATURES requests
*
* Note: This is a private function, intended for internal
* use by the USB stack, when processing SET/CLEAR
* feature requests.
*******************************************************************/
static void USBStdFeatureReqHandler(void)
{
BDT_ENTRY *p;
EP_STATUS current_ep_data;
#if defined(__C32__)
DWORD* pUEP;
#else
unsigned char* pUEP;
#endif
#ifdef USB_SUPPORT_OTG
//Check for USB On-The-Go (OTG) specific requests
if ((SetupPkt.bFeature == OTG_FEATURE_B_HNP_ENABLE)&&
(SetupPkt.Recipient == USB_SETUP_RECIPIENT_DEVICE_BITFIELD))
{
inPipes[0].info.bits.busy = 1;
if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
USBOTGEnableHnp();
else
USBOTGDisableHnp();
}
if ((SetupPkt.bFeature == OTG_FEATURE_A_HNP_SUPPORT)&&
(SetupPkt.Recipient == USB_SETUP_RECIPIENT_DEVICE_BITFIELD))
{
inPipes[0].info.bits.busy = 1;
if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
USBOTGEnableSupportHnp();
else
USBOTGDisableSupportHnp();
}
if ((SetupPkt.bFeature == OTG_FEATURE_A_ALT_HNP_SUPPORT)&&
(SetupPkt.Recipient == USB_SETUP_RECIPIENT_DEVICE_BITFIELD))
{
inPipes[0].info.bits.busy = 1;
if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
USBOTGEnableAltHnp();
else
USBOTGDisableAltHnp();
}
#endif //#ifdef USB_SUPPORT_OTG
//Check if the host sent a valid SET or CLEAR feature (remote wakeup) request.
if((SetupPkt.bFeature == USB_FEATURE_DEVICE_REMOTE_WAKEUP)&&
(SetupPkt.Recipient == USB_SETUP_RECIPIENT_DEVICE_BITFIELD))
{
inPipes[0].info.bits.busy = 1;
if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
RemoteWakeup = TRUE;
else
RemoteWakeup = FALSE;
}//end if
//Check if the host sent a valid SET or CLEAR endpoint halt request.
if((SetupPkt.bFeature == USB_FEATURE_ENDPOINT_HALT)&&
(SetupPkt.Recipient == USB_SETUP_RECIPIENT_ENDPOINT_BITFIELD)&&
(SetupPkt.EPNum != 0) && (SetupPkt.EPNum <= USB_MAX_EP_NUMBER)&&
(USBDeviceState == CONFIGURED_STATE))
{
//The request was valid. Take control of the control transfer and
//perform the host requested action.
inPipes[0].info.bits.busy = 1;
//Fetch a pointer to the BDT that the host wants to SET/CLEAR halt on.
if(SetupPkt.EPDir == OUT_FROM_HOST)
{
p = (BDT_ENTRY*)pBDTEntryOut[SetupPkt.EPNum];
current_ep_data.Val = ep_data_out[SetupPkt.EPNum].Val;
}
else
{
p = (BDT_ENTRY*)pBDTEntryIn[SetupPkt.EPNum];
current_ep_data.Val = ep_data_in[SetupPkt.EPNum].Val;
}
//If ping pong buffering is enabled on the requested endpoint, need
//to point to the one that is the active BDT entry which the SIE will
//use for the next attempted transaction on that EP number.
#if (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0) || (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG)
if(current_ep_data.bits.ping_pong_state == 0) //Check if even
{
USBHALPingPongSetToEven(&p);
}
else //else must have been odd
{
USBHALPingPongSetToOdd(&p);
}
#endif
//Update the BDT pointers with the new, next entry based on the feature
// request
if(SetupPkt.EPDir == OUT_FROM_HOST)
{
pBDTEntryOut[SetupPkt.EPNum] = (volatile BDT_ENTRY *)p;
}
else
{
pBDTEntryIn[SetupPkt.EPNum] = (volatile BDT_ENTRY *)p;
}
//Check if it was a SET_FEATURE endpoint halt request
if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
{
if(p->STAT.UOWN == 1)
{
//Mark that we are terminating this transfer and that the user
// needs to be notified later
if(SetupPkt.EPDir == OUT_FROM_HOST)
{
ep_data_out[SetupPkt.EPNum].bits.transfer_terminated = 1;
}
else
{
ep_data_in[SetupPkt.EPNum].bits.transfer_terminated = 1;
}
}
//Then STALL the endpoint
p->STAT.Val |= _USIE|_BSTALL;
}//if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
else
{
//Else the request must have been a CLEAR_FEATURE endpoint halt.
#if (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0) || (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG)
//toggle over the to the non-active BDT
USBAdvancePingPongBuffer(&p);
if(p->STAT.UOWN == 1)
{
//Clear UOWN and set DTS state so it will be correct the next time
//the application firmware uses USBTransferOnePacket() on the EP.
p->STAT.Val &= (~_USIE); //Clear UOWN bit
p->STAT.Val |= _DAT1; //Set DTS to DATA1
USB_TRANSFER_TERMINATED_HANDLER(EVENT_TRANSFER_TERMINATED,p,sizeof(p));
}
else
{
//UOWN already clear, but still need to set DTS to DATA1
p->STAT.Val |= _DAT1;
}
//toggle back to the active BDT (the one the SIE is currently looking at
//and will use for the next successful transaction to take place on the EP
USBAdvancePingPongBuffer(&p);
//Check if we are currently terminating, or have previously terminated
//a transaction on the given endpoint. If so, need to clear UOWN,
//set DTS to the proper state, and call the application callback
//function.
if((current_ep_data.bits.transfer_terminated != 0) || (p->STAT.UOWN == 1))
{
if(SetupPkt.EPDir == OUT_FROM_HOST)
{
ep_data_out[SetupPkt.EPNum].bits.transfer_terminated = 0;
}
else
{
ep_data_in[SetupPkt.EPNum].bits.transfer_terminated = 0;
}
//clear UOWN, clear DTS to DATA0, and finally remove the STALL condition
p->STAT.Val &= ~(_USIE | _DAT1 | _BSTALL);
//Call the application event handler callback function, so it can
//decide if the endpoint should get re-armed again or not.
USB_TRANSFER_TERMINATED_HANDLER(EVENT_TRANSFER_TERMINATED,p,sizeof(p));
}
else
{
//clear UOWN, clear DTS to DATA0, and finally remove the STALL condition
p->STAT.Val &= ~(_USIE | _DAT1 | _BSTALL);
}
#else //else we must not be using ping-pong buffering on the requested endpoint
//Check if we need to call the user transfer terminated event callback function.
//We should call the callback, if the endpoint was previously terminated,
//or the endpoint is currently armed, and the host is performing clear
//endpoint halt, even though the endpoint wasn't stalled.
if((current_ep_data.bits.transfer_terminated != 0) || (p->STAT.UOWN == 1))
{
//We are going to call the user transfer terminated callback.
//Clear the flag so we know we took care of it and don't need
//to call it again later.
if(SetupPkt.EPDir == OUT_FROM_HOST)
{
ep_data_out[SetupPkt.EPNum].bits.transfer_terminated = 0;
}
else
{
ep_data_in[SetupPkt.EPNum].bits.transfer_terminated = 0;
}
//Clear UOWN and remove the STALL condition.
// In this case we also need to set the DTS bit to 1 so that
// it toggles to DATA0 the next time the application firmware
// calls USBTransferOnePacket() (or equivalent macro).
p->STAT.Val &= ~(_USIE | _BSTALL);
p->STAT.Val |= _DAT1;
//Let the application firmware know a transaction just
//got terminated by the host, and that it is now free to
//re-arm the endpoint or do other tasks if desired.
USB_TRANSFER_TERMINATED_HANDLER(EVENT_TRANSFER_TERMINATED,p,sizeof(p));
}
else
{
//Clear UOWN and remove the STALL condition.
// In this case we also need to set the DTS bit to 1 so that
// it toggles to DATA0 the next time the application firmware
// calls USBTransferOnePacket() (or equivalent macro).
p->STAT.Val &= ~(_USIE | _BSTALL);
p->STAT.Val |= _DAT1;
}
#endif //end of #if (USB_PING_PONG_MODE == USB_PING_PONG__ALL_BUT_EP0) || (USB_PING_PONG_MODE == USB_PING_PONG__FULL_PING_PONG)
//Get a pointer to the appropriate UEPn register
#if defined(__C32__)
pUEP = (DWORD*)(&U1EP0);
pUEP += (SetupPkt.EPNum*4);
#else
pUEP = (unsigned char*)(&U1EP0+SetupPkt.EPNum);
#endif
//Clear the STALL bit in the UEP register
*pUEP &= ~UEP_STALL;
}//end if(SetupPkt.bRequest == USB_REQUEST_SET_FEATURE)
}//end if (lots of checks for set/clear endpoint halt)
}//end USBStdFeatureReqHandler
/** EOF USBDevice.c *****************************************************/