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P. Short
06-04-2007, 09:50 PM
Some time back I modified the Renard firmware so that it could be used to receive DMX data. There have been so many things going on, though, that I stopped working on that project after some initial testing of the firmware. I didn't have any true source of DMX, so I just programmed a small PIC to bit-bang data that looked like DMX (and verified it somewhat with a scope).

The best hardware for this firmware would be a Renard8 board with an adaptor cable (and the usual external SSRs). In that particular case it doesn't even need the external oscillator, as the standard 8 MHz clock divides down nicely to 250,000 hz.

Right now I don't intend to do anything with this project, because I have too many other Renard variants here. But if I were going to continue the project, I would create a PCB with the zero-crossing circuit on it, along with the standard DMX connectors. I would also further modify the firmware so that the address could be programmed into the PIC through the comms port, rather than just through the programmer.

If anyone wants to adopt this project, I would be fine with that.

--

Phil

DynamoBen
06-04-2007, 10:03 PM
Fair enough. I'm at the point in my project where I have a single LED dimming up and down perfectly via DMX. I'm working in PICBasic, not assembly, so I had to figure out how to make it all happen in my "native" language.

The goal was to create the DMX reception code so I could recycle it for use in multiple devices (anything I can dream up). My Short term goal is to control a fogger I own that doesn't currently run on DMX and create some dimmers.

Phil since the DMX side is done I may adopt your schematic and dimming methods.