Home Page Forums MAME MAME thread about ARC CPU cores

so uhhhhhhhhhhhh, we were talking (or more precisely, i was talking to other MAME devs) on the shoutchat about what CPU cores to pick until Al Kossow said that "starting a thread about cores is SO much better than walking away for 1/2 an hour and seeing half of the discussion gone".

so i'm doing just that. someone requested on the shoutchat about which cpu cores that person should be working on for mame... i wanted to participate but asked for some help and i was presented with two CPUs that "deserved some love" - ARCtangent and ARCcompact (hope i've spelled those two right!). after some discussion, said person decided to go with the former.

if there's any other CPU core that you think deserves some love or at least some sort of polish, please let your voice be known right here!

mcs51, but it's going to be nontrivial. Not only the cpu is harvard and annoying (memory-mapped registers!), but there's a trillion variants so there's a need for extreme flexibility.

Wasn't AJR working on mcs51? Or planning to?

I think somebody was, because I was somewhat relieved to be able to drop looking at the Leapfrog IQuest / Turbo Twist stuff, which seemed to be failing on some kind of peripherals on whatever variant they have in the glob.

I guess that explains why none of the terminals that use mcs51s are simulated.

I have some mcs51 in-circuit emulators, which adds an extra layer of nightmare fuel to what could be done

Speaking of MCS-51, wasn't some refactor or other - possibly the conversion of the MC68681 DUART to use diserial - responsible for audio issues being introduced in the Microprose 3D games ages ago? I'm not sure if the best solution would be to make MCS-51 also use diserial, implement a better version of diserial, or make the DUART use a custom serial implementation once again.

Correct. MCS-51 has never spoken bit-serial, so the Microprose games were left out when the rest of MAME was converted. AJR claimed to do the serial right on the MCS-51 you'd have to rewrite the entire core due to some unique semantics it has but I don't know the details.

As a possibility for interested parties, besides 80960KA/KB, are any other i960 variants currently needed or supported?

I don't know of any dumps for anything that used non K-series i960s off the top of my head. I've read a couple of times that i960s were popular in some laser printers.