1024MAK wrote:Well, Sinclair describes the QL as having two processors...
We're in violent agreement. How these things were seen then and how they are seen now are quite different.
The 8049 is a quite poor microcontroller. It's not a "CPU" in that it's not the 'central' arbiter and controller - it just repeats a loop. It IS a processor. That said, the 8049 is a really useful chip, which is why it is still made today.
I'd still think there is a place for keeping an IPC or I/O chip or even potentially more of them, and making the QL's IPC system just a smaller part of something larger.
There is a trap for IPC, and known specifications for that trap to handle the current IPC communications, so from the high level, there are some simple commands to handle keyboard / sound / serial (I still think serial should be a separate thing, so that potentially might free up some command handles)
How the actual hardware of an IPC is realised is then not relevant to QDOS or any other program - so it could easily be done as DP ram or fast serial or whatever you want. You could then hang off what ever logic you wanted on the I/O side - why just one processor - you could have more...