Building Sensor Watch Firmware

Install the cross-compiling toolchain on Linux

• Debian/Ubuntu: apt install gcc-arm-none-eabi libnewlib-arm-none-eabi

• Archlinux: pacman -S arm-none-eabi-gcc arm-none-eabi-newlib

Other Linux:

• Download the GNU ARM Embedded Toolchain for 64-bit Linux
• Extract it: tar xjf gcc-arm-none-eabi-10.3-2021.10-x86_64-linux.tar.bz2
• Add it to your PATH: export PATH="$PATH:/path/to/extracted/gcc-arm-none-eabi-10.3-2021.10/bin"

Note: if you want, you can add the above PATH export to your shell’s startup script to make it persist between shell invocations

Install the cross-compiling toolchain on MacOS

• Download the GNU ARM Embedded Toolchain for 64-bit MacOS
• Double-click the installer and follow the prompts to install the toolchain
• Add the toolchain to your PATH: export PATH="$PATH:/Applications/ARM/bin"

Note: if you want, you can add the above PATH export to your shell’s startup script to make it persist between shell invocations

Install the cross-compiling toolchain on Windows

• Download the GNU ARM Embedded Toolchain for Windows

• Install

• On the final screen choose the option to add to path

• if you dont, then the readme has instructions to set the path

• Download GnuCoreUtilities

• Install and add to path

• set PATH="C:\Program Files (x86)\GnuWin32\bin";%PATH%

• Create an alias

• doskey gmkdir="C:\Program Files (x86)\GnuWin32\bin\mkdir" $*

• Download GnuMake

• Install and add to path

• set PATH="C:\Program Files (x86)\GnuWin32\bin";%PATH%

• Download Python

• Install and add to path

• Create an alias

• doskey python3="C:\Users\dgran\AppData\Local\Programs\Python\Python312\python" $*

Compile firmware

• From within the repo:
• make BOARD=X DISPLAY=y, with X and Y replaced with the following:
  • For Sensor Watch Pro boards make BOARD=sensorwatch_pro
  • For Sensor Watch Lite boards make BOARD=sensorwatch_red
  • For classic green or blue boards, make BOARD=sensorwatch_green or make BOARD=sensorwatch_blue
  • If you are using the original LCD that came with the Casio, add DISPLAY=classic
  • Otherwise, add DISPLAY=custom

The built firmware will be at build/firmware.uf2. You can now flash this firmware to your watch.

“I just want to pick my own set of watchfaces”

The list of included watchfaces can be found in the watch_faces array in movement_config.h. Simply add, remove, and/or rearrange faces in this list to your liking and re-compile/re-flash your firmware.

An official web-based builder for Second Movement, forked from the previous unofficial online firmware builder, is forthcoming. Watch this space.