Amstrad CPC NOP (No Op)Generator ?

[SerErris]

Hmm, you are right, I did not thought about the IORQs...

But M1 would also not give you the right thing, as you would not see any additional bytes of the operation. So for instance LD HL,&4000 would consist of a 3 byte command (opcode + 2 address bytes). If you monitor the M1 line, you would only see the opcode byte address, but not the other two addresses.

So you would actually need to monitor the MRQ (memory request) line to capture all memory reads. That will then give you everything, but still that does not work very well with a logic probe or a oscilloscope.