I've been needing to read out some vintage PROMs for a project to emulate a quantel paintbox within MAME
i have a TL866 programmer but it doesn't directly support many of these old PROMs so i have been making up adaptors to convert the pinout to something basic like a AM2716 which is supported, i then edit the results in a hex editor to account for differences in length etc as all these devices are all smaller than the 2716, this has worked really well on several other devices (27S19, 63S441, 27S33, 28L22) but i am having issues reading a AM27S29, every time i read it i get a different output.
I have checked and rechecked my wiring and can't see any errors, shorts or bad connections etc
Does the collective have any suggestions as to what's going wrong?