A bit of all, H is (re)stored after this instruction.
Why is this the solution? This is same memory reading.
The timing must be the same, but B gets a value that is not allowed.zsolt wrote: ↑Tue Sep 12, 2017 4:58 pmHi,Why is this the solution? This is same memory reading.
CP (HL) might work too, but it does effect the Z-flag where LD H,(HL) has no effect on flags but still use 7 tstates in 1 command and 1 byte.
regards Andy .
OK, it is time-correct, but does not solve the original "problem":
(if it is a real problem)sirmorris wrote: * Yes, the ZX81 appears to have a pet - a restless red 'ant' (escaped from the classic game?) which relentlessly patrols RAM from the end to the start. It's (most likely) a read instruction in the display routine.
Andy, what should I see there?