At the moment theres 2 protocols for digital module control behind the panel, I2C and the ‘select bus’, which is employed by Malekko, Make Noise, Expert Sleepers and a few others.
Im thinking lets join them together.
I did some research yesterday on the Select Bus protocol, and its a bit patchy, but basically the protocol is sending MIDI program change messages into the generally unused CV/Gate bus. Luckily the reccomended hardware implementation for doing this safely is right there in the Tempi and Rene Mk2 manuals!
Make Noise implementation in Tempi and Rene Mk2. You can see that the Select Bus allows setting the States of either of these modules, and they can be configured to either send or recieve state changes
My vision for this is to begin with select bus scene recall via Teletype OPs. This would enable setting Distings to different algorithms and parameters per TT scene, as well as TEMPI, Rene Mk2 and the Malekko stuff. I was thinking about implementing this on a ‘enhanced’ TT busboard, rather than having a floating pcb mounted in the case. A small MCU is needed to translate I2C to serial MIDI, which could live on the backpack, and then use a 16pin power connector to get the messages on the bus.
At the moment, I have a few Disting Mk4’s on the way for experimenting, as well as the parts reccomended by MN for the buffering. Probably late next week I’ll put together a simple thing on a breadboard to send the required MIDI messages and see if I can get the Distings to react, and then after that is OPs on the TT side.
The reason im posting at length here before just implementing it is to gauge community interest and to do this in a manner that meshes well with the Teletype code base. While I have the Teletype toolchain installed and compiling, Im only a casual programmer at best and so I don’t want to go adding my own OPs for this in the wrong way, particularly if a few people think this is a neat idea. Also I dont actually own most of these Select Bus enabled modules, so ill need to find a few keen people to test combinations I cannot.
Rough Select Bus reference from Macro Machines (I think):
Make Noise Select Bus commands: