04 March 2023 - 10 March 2023

An apparent mismatch between GCC register model and ACK stack model preclues an EM backend. Between fighting byte-addressability and machine models, it appears that working with GCC is a losing battle. Investigating a more direct approach with a standalone GNAT build (like gnat-llvm) with https://github.com/libfirm/libfirm libfirm for parse tree and code generation.

One should not be disappointed that a guitar can't sound like a flute.

Create verilog models for 2903/2910 and verify against hardware?

…Along with standard 8 bit loader

6809 1000ns maximum cycle time too short

Reverse engineered some of a mostly fully built development board with one part missing. As near as I can tell, that one part is some sort of programmable address decoder with a pinout that does not correspond to any part I can find. Kind of like a GAL but with inputs on top and outputs on bottom (as opposed to left and right in a standard GAL). I have no idea what the provenance of this board is and if it ever worked.

Full debug fails - not enough disk or memory.

Good excuse for floating point ALU design. Try posit format?

May be useful for handbuilt and rare systems (DMX1000?).