I2C for display

Added by parag0n almost 9 years ago

One of my main bugbears with the Laos system is the use of i2c for the comms to the display. I2C isn't massively tolerant of noise, and freezing i2c displays causing job failures has been one of my biggest issues with the Laos conversions I have done. The noise and the lack of support on the atmega for i2c clock stretching mode makes the i2c a bit flakey.

As the i2c pins on the mbed are also serial port 3, and the display board itself has an ftdi connector on it, it would be theoretically possible to switch to serial comms at 9600 baud, by making up the correct adaptor cable and removing the 2k2 pullups. Serial appears to be far better suited to a high noise environment such as in a laser cutter.

Has anyone tried this, and what would be the best way to look at implementing such a fundamental change? I'm guessing at the least I'd need to reimplement laosdisplay and change how the display is configured in config.ini