ColorCNC Colorlight 5A-75E/5A-75B as FPGA controller board

• install LiteX to generate the code

mkdir LiteX && \
    cd LiteX && \
    wget https://raw.githubusercontent.com/enjoy-digital/litex/master/litex_setup.py && \
    pip3 install --user  meson ninja && \
    python3 litex_setup.py --init --install --config=standard --gcc=riscv

• install yosys for building to the target ECP5.

    wget https://github.com/YosysHQ/oss-cad-suite-build/releases/download/2022-02-27/oss-cad-suite-linux-x64-20220227.tgz  && \
    tar -xvf oss-cad-suite-linux-x64-20220227.tgz -C /opt/ && \
    rm oss-cad-suite-linux-x64-20220227.tgz  && \
    echo '# set PATH so it includes oss-cad-suite' >> /etc/profile && \
    echo 'if [ -d "/opt/oss-cad-suite/bin" ] ; then' >> /etc/profile && \
    echo 'PATH="/opt/oss-cad-suite/bin:$PATH"' >> /etc/profile && \
    echo 'fi' >> /etc/profile

• create a configuration file which suits your machine (see for some examples the ./examples directory in the repository)
• generate the code (assuming you are in the terminal in the root of the repository) and build it when successful

python -m firmware path/to/your/config/file
cd [i]card_name[/i]/gateware
chmod +x ./build_colorlight_5a_75e.sh
./build_colorlight_5a_75e.sh

DePrutser wrote:

[...]

When I got it working, I'm planning on extending your README.md and sending a pull request.

Cheers,
Cedric
 

• the pick-off (the position of the fixed point) can be set (in code for now, if people want I can make it also user-configurable) with different settings for position, velocity and acceleration. This gives some smoother behavior on the stepper motor. For example, if I use the same pick-off for speed and position, the maximum speed attained will be a step with every clock of the FPGA (50 MHz in my case). This is ridiculously fast and as far as I know there is know stepper driver capable of doing this. The lowest step frequency will be 1 / 2^32 step per clock cycle, which boils down to 0.01 step per second. Especially with very low speeds or with ramping down this might lead to some vibrations. Therefor, the pickoff for velocity is now shifted with an additional 8 bits. The maximum step frequency now becomes 195 kHz, which is reasonable high and close to the max frequency of for example standard Leadshine or Lichuan driver (checked with the DM542). The minimum speed is now 0.00003 steps per second. Audibly this results in a much smoother running of the stepper motor.
• the pick-off for acceleration was already shifted by 16 bits, otherwise it would be always zero. It is now also easy to re-configure this to another value.
• In the firmware the shift of the acceleration relative to the position determines the extra bytes required. For a relative shift of 16 bits, this will consume 3 bytes of extra 'space' for the registers.
• because above lead to changes in both firmware and driver, the version number is bumped. This version number will prevent users from combining incompatible firmware and driver.