On Feb 25, 2:09 am, Steven Hirsch <snhir...@gmail.com> wrote: > Does anyone know if the MMI PROM on older Disk ][ controllers has the same > pinout as any of the 74S* programmable PROMs? I'd like to read the contents, > but would prefer not to let the magic smoke out of my programmer. According to my Xref databook, the 6309 has the same pinout as DM74LS471 and N82S136N and a few others.