brainwagon

Fellow hacker Eric Smith has released the code for an 8080 simulator. I spent a few hours hacking my own 8080 emulator a few months ago, and at least got it to run Tiny BASIC, but I was never quite successful in getting it to boot CP/M. Among some of the problems were that I wasn’t quite assured that I implemented all the opcodes properly. There are some programs which act as an “opcode exerciser”, and produce a series of checksums that you can use to detect bugs, but I found that even well known simulators like simh didn’t match the output from real 8080s. It appears that Eric has done the heavy lifting and figured this stuff out, and released the fruits of his labor as a GPL’ed reference implementation, checked against the actual running against an original Sol20. I’ll have to go back sometime and see where my own simulator has gone awry, but until then, thanks Eric!

ksim 8080 simulator released | What's All This Brouhaha?.