As some of you know, there has not been an update for MAME on CoCo-Pi since version 0.254. This is because it no longer compiles successfully on 32bit systems (buster based) for the Raspberry Pi. It fails with something in the 7zip libraries and no mount of tinkering has helped. I’m not the only one having this issue. mizpaf on AtariAge (forum) maintains the code of the TI-99/4a driver and noticed this issue as well when he was compiling for the 32bit ARM/Raspberry Pi platform. He came to the same conclusion I did which was to move on the latest Raspberry Pi OS (bullseye) and to 64bit (you can read more about his findings here):
For now, I will continue to update the current CoCo-Pi 32bit unified version but without new versions of MAME. If there are updates to the CoCo/Dragon/MC-10 drivers (or cousins) I may be able to backport (some of) them to version 0.254, but no promises. The good news is that XRoar is an excellent option for emulation and remains current in CoCo-Pi. TRS80GP is another nice option (for CoCo 1 and 2). OVCC remains in CoCo-Pi for CoCo 3 emulation.
As for the future of this verion of CoCo-Pi, my intention is to keep it updated until (at least) the end of the year. My focus has been to get the new 64bit version of CoCo-Pi completed and I’m very close to a release for it. The current versions of MAME compile and run just fine in 64bit. The “look and feel” of the 64bit version of CoCo-Pi is just about the same as what you are used to now, no big learning curve will be required. RPi3, RPi4 and RPi400 platforms will continue to be supported in 64bit.