Hello all,
I totally forgot to post on here about my firmware for the SCC and Domoticz!
Here it is:
https://github.com/codeaholics/evofw2If you're familiar with building the CULFW firmware for SCC, then building my firmware will be straightforward - it's the same Makefile!
A lot of the concepts are taken from the FullTalgoRythm firmware, but following recent conversations with DanD and bruce_miranda, I think the message parsing in mine is much tighter. Specifically, I think it will handle most, if not all, of the odd variants that people have been talking about recently.
The USB interface runs at 38,400, while Domoticz expects 115,200. It's impossible to get this board to run at 115,200 reliably because of the 8MHz crystal and the way the Atmel atmega1284p MCU derives the serial clock from it. So you'll need the latest version of Domoticz (from source code) which includes a patch to allow the baud rate to be selected when creating or updating the Evohome interface. Sometime soon, I will increase the baud rate to 76,800 to give a little bit more headroom.
I am interested in exploring colintd's CULFW modifications. It appears as though this uses the MCU's second USART to interface with the CC1101. I wanted to take that approach, but couldn't get any information from the SCC manufacturers (busware.de) about how the CC1101 pins were wired to the MCU pins. I know (because my firmware works!) that they're wired to PB1 & PB2, but if colintd's approach works too then this would suggest they're also wired to PD for the second USART. If I can make this work it will significantly cut down on the work being done by the MCU which currently processes bits off the radio one-by-one and probably loses sync because it attempts to do so synchronously with no accounting for drift and/or timing errors, which I assume the hardware USART will take care of.