On Apr 21, 2024, at 08:08, Mike Katz via cctalk <cctalk(a)classiccmp.org> wrote: Well my PDP-8 was built in 1974 and is still running (with careful maintenance). My PiDP-8/I has been up and running continuously with a Raspberry PI 3B running it for about 5 years now. My PiDP-11 has been up and running with a PI-4B for more than 4 years continuously. Though I agree with your comment that the PDP-8 was built to last (just ignore the disintegrated foam used between the motherboard and the case or on the case top) I have PCs that are more than 10 years old that are still running. As for the RP2040 being cheap crap, I beg to differ with you. It is a solid chip, produced in 10s of millions at least. And, I would bet, a better quality chip than your Z-80, if due only to improved IC manufacturing technologies. Just because it's old doesn't make it good. I worked on a 32KHz 4 Bit CPU (about 20 years ago) where the development hardware was very unstable and the tool chain not a whole lot better. Early Microsoft and Lattice C compilers for the PC were buggy as hell. If you want I can list a few bugs from each of them in another thread. One of the biggest features of the Z-80, the extra register set, was rarely used in open source software in order to maintain compatibility with the 8080. Some of the early Z-80 CP/M tools did not work because they were derived from 8080 tools. After time the tools got better. That is the case with any piece of software. If it doesn't become obsolete and if maintained it will get better over time.