Renard Firmware
There are two versions of the firmware available for use in slightly different circumstances. They will both work on all of the Renard boards (except the Ren-C board, which has its own firmware). They all use version 1 of the Renard protocol, and operate at 57600 baud.
The first (regular) version of the firmware causes a narrow output pulse (30 &muS, or so) to turn on the SSRs. This results in the lowest PCB current requirements, because the waveform driving each SSR has a 1:256 duty cycle. The drawbacks to this version is that it will not properly control any channel status LEDs (present only on the Renard64 board), and may cause some issues when driving LED strings (e.g. they may possibly not turn on at the upper 25% of the brightness range).
The second (PWM) version of the firmware sends a variable-width output pulse to turn on the SSRs (the output turns on at a variable time in the AC power cycle, and stays on until the end of the cycle). This presents a PWM signal to any attached channel status LEDs, causing them to have a variable brightness that somewhat corresponds to the brightness of lamps attached to the SSRs. It will also be better at driving LED strings on the output of the SSR (because the PIC drives the SSRs throughout the cycle, rather than relying on the current through the opto-isolator to latch the opto).