Firmware Upgrade

The TTA8 basically does not have OpCode like typical CPUs. It has a few micro-codes that are quite limited and rather difficult to use. The Interpreter reads "OpCode" and calls a subroutine. The CPU model is also simulated.

The "Firmware Upgrade" as mostly about adding more registers to the System area. This unfortunately changes almost all of the existing register addresses. The reason was that I need more space near the top of memory for long pointer moves (to allow for writing to FRAM).

Anyway, its done now. More registers will be added later but they will be below the System area and will not affect much.

Serial IO Board

Sent away a new Serial IO Board. Swapped out the 74HC93 for a 74HC161. The 74HC93 is rather rare nowadays (even though I have two spare).

Serial Monitor

The next firmware upgrade will be the addition of a serial monitor.

ZIF Sockets

I am definitely going to make a new programmer and Paged Memory Board with a ZIF sockets. I don't know why I have not done this so far. I suppose I never expected to need to reprogram the chips so many times.

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Termination Board

Assembled the thermination board and added it to the back of the mother board.

Not sure how to test it. Parhaps if I find and AM radio I can listen to the CPU noise with and without.

Serial Board

Assembled the new serial board.

ZIF Sockets

They don't fit, the holes are too small. I will have to redo the Programmer and the Paged Memory boards with larger holes.

Coding

Coding has stopped until I get my laptop back. It decide not to boot up one morming.

AlanX