Hi everyone,
Reading the Z80 documentation, I'm wondering if the extra WAIT signal is used on every instruction. There's a first WAIT signal poll from the CPU on fetching the instruction from memory, but that seems to be included in the M1 cycle.
Apart from that, it seems to me that the extra WAIT signal is only needed if the instruction accesses the memory.
That's important to know. Let's see those 2 examples :
ld a,(memory)
exx ld a,b exx
If an extra WAIT signal is needed on all operations, than the second code is slower than the first : (4+1+4+1+4+1)=15 clock cycles versus (13+1)=14. If not, than the first code is slower : (13+1)=14 versus (4+4+4)=12.
What do you think ?
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nevermind that M1 and T-states stuff if you don't understand it.