-----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Jan Adelsbach Sent: Thursday, July 30, 2015 3:32 PM To: General Discussion: On-Topic and Off-Topic Posts Subject: PDP-1 in Verilog (Incomplete) + More Hi all, At the time I've released my DG NOVA in Verilog I was also working on a PDP-1 in Verilog. Since I haven't touched the thing for quite some time I've decided to just release it before it catches dust. So far it can execute all kinds of programs, limitation is that they may not use IO as I haven't implemented the latter yet. (So essentially the same state as my DG NOVA implementation) It also supports optionally some PDP-1D features in the OPR and SKP instruction groups. Interrupts are implemented but untested. I'm not sure in which state I left the IOT controller if it works then both SBS and SBS16 might be usable. TL;DR: https://github.com/Jside/pdp1 The RCA110 was the project I was working on before I started the DG NOVA, it can execute some instructions but there is to much ambiguity in the reference manual on bitsavers in some cases which led me to abandon it. Especially since there is no software to cross-check. So for reference you can get it here: https://github.com/Jside/rca110 I wanted to mess around a bit with Chisel (a new HDL language used by the RISCV project) so here is the start of a CDC160 (currently only the instruction decoder): https://github.com/Jside/cdc160 I've also uploaded my DG NOVA to Github: https://github.com/Jside/nova1 MC14500B anyone? http://janadelsbach.com/soft/mc14500b.tar I will occasionally continue working on both the NOVA and PDP-1 (and maybe CDC160?). Also pull requests are welcome. As is obvious I *really* like implementing old computers in HDL languages but I always get stuck around IO since for any kind of flexibility as with an emulator I essentially would need to write a bus wrapper so that a (soft-core) processor executing Linux running an IO server could handle i.e. hard disks and magnetic tapes and that's I think really not worth it. So I might just go over and contribute to an emulator/simulator like SIMH if I'm in an must-implement-an-old-computer/processor mood ;). Regards, Jan