2 ms·
I have been playing around with my own design, initially inspired by the gigatron, but it seems to have diverged somewhat. ALU is the same, address unit enhance
by Lerc 1y ago
I have been playing around with my own design, initially inspired by the gigatron, but it seems to have diverged somewhat. ALU is the same, address unit enhanced, but a lot of the rest, program counter and instruction decode ending up completely different. Shuffling the Harvard architecture to be more like a instruction cache, only 16 bytes of instruction memory with long jumps triggering a full instruction memory load from RAM.
Going for transport triggered architecture for additional features seems like a fairly easy win. I kind of started designing one before I realised that's what the design was. The Gigatron has to do some unreasonably hard work for a few operations, like shift right, which is an operation that can fundamentally be done with just wires once you have a mechanism to provide the input and fetch the output.
Definitely not knocking the Gigatron though. Every limitation it has is because it saved a chip, when it comes something minimal to build upon It's pretty cool.