CasiOS

The watch firmware is written in C and compiled with Microchip’s xc8 compiler. Functionality is separated into ‘mode’ applications, with each mode implementing a set of procedures to be run when active. The active mode is changed by the Mode side button, with each press cycling through an array of modes.

Requirements

The following programs are required to build and flash the firmware: - make - xc8 - Microchip’s C compiler for PICx Devices - picchick - Flash PICs using an AVR device. Get it from the repo.

Configuration

Build Options

These options modify things about the firmware at build time and can be found in the Makefile: - MODES - A list of modes to compile into the firmware. - PCB_REV - PCB Major version number. Changes some pins and which clock to use. - LOG_LVL - Sets the amount of logged information. Logs above the specified level are not compiled into the final firmware, so expect things to run differently. A log level of ‘0’ is recommend for builds that are going into a watch for use. - XTAL_FREQ - The frequency in Hertz of the oscillator. Changing this value DOES change the frequency of the internal oscillator! - BOOT_OFFSET - Offset for bootloader. Set to 0 if not using a bootloader.

Library Config

Some libraries have their own configuration options. These can be found in the corresponding header files in src/lib/: - logging.h - LOGGING_UART_BAUDRATE - The baud rate of the debug UART connection.

Programmer Config

Configure the serial device to use in the Makefile. This should be a 1-wire capable serial converter. - PROGRAMMER_PORT - Serial port of picchick compatible programmer. e.g. /dev/ttyUSB0 or COM3 - PROGRAMMER_BAUD - Baud rate of programmer serial connection. - PROGRAMMER_FLAGS - Additional programmer flags to use.

Configuring Modes

To configre which modes are built into the firmware, edit the modes.cfg file located in src/modes/. Each mode’s source files, header files, and mode_app_t struct should have the same name which corresponds to the name used in the config file.

Building

Compilation is achieved with the make utility. A run of the make fw command will produce a CasiOS.hex file in the sub-directory build/. The command make clean will delete all built files, and a make fclean will remove all files and created directories.

make [fw]       # Build firmware with settings defined in Makefile
make clean      # Remove built firmware files
make fclean     # Remove all created files and folders

The header file src/modes/mode_config.h is automatically generated with the make config command. The generated files can be removed with make cclean. Note that the config is generated automatically with make fw and removed with a make fclean.

make config     # Generate config files
make cclean     # Remove generated files

Upload

Python utility picchick is used by the Makefile in conjuction with flipflop to upload firmware. It requires a serial device connected to the PowerPIC’s Debug and Ground pins. For further information about uploading firmware checkout flipflop, the bootloader used for the PowerPIC.

After configuring the serial device in the Makefile, make upload should upload the firmware to the watch. Don’t forget to enter the bootloader by resetting the watch!

make upload      # Upload firmware using picchick