Super, a network pro goes into the dance
very interesting document!
I recognize some elements, there is a lot of similarity (ioreg, commram, operation flow)
I do not know if you have already watched the operation on model3, but you risk to navigate in known world
Another thing, to fix dirt with 3 and 4 players, I had to use what I thought was the machine number: commram [0x0002] (aka shared ram)
ie: dirt with master slave1 salve2 I've got
M sends 0x02 0xff 0x03 0x03 0x03 0x03
S1 sends 0x02 0xff 0x03 0x03 0x02 0x02
S2 sends 0x02 0xff 0x03 0x03 0x01 0x01
commram [0x0002] = num of machines
commram [0x0003] = num of master slave machine (sat not include) ??
commram [0x0004] = id
commram [0x0005] = packet destination?