Has anyone dumped the microcode of the PDP-11/05? I am looking into a CPU board pair that are not behaving that well. The only switch that does anything is the START switch. The rest is doing nothing. The CPU clock is stopped.
When tracing the microprogram flow it looks very suspicious. Comparing the same sequence with a better working pair reveal a few differences. All these can be narrowed down to one single PROM chip. It doesn't look like it is something else that is wire-ored onto the micor address bus since the enable signals for all those are inactive. And one signal is already low so wire-ORing would not change it. I would need a dump of the chips or at least A04A2 / E102 on the Control board. There are microcode listings in the manual but they need to be treated to get into a dump. So if someone already have a dump that would be highly appreciated. /Mattis
