Grrr...

A very frustrating day, first I blew my last LCD panel by getting the power connections mixed up...

Then about 6 hours trying to figure out an intermittent problem that has now become permanent:

• Stepping through program slowly / by hand register contents are random
• Sometimes works at full speed
  
• Sometimes randomly jumps out of program

Tomorrow will have a few checks:

• Is interupt /NMI getting generated? I've not noticed any IORQ + M1s - these lines should be pulled high
  
• Is ROM corrupted - had trouble then it worked then trouble so doubt its the ROM
• More decoupling!
• Buffer memory data bus?

Very frustrating!