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Z80 Known Bugs..

By: Howard Goldstein - HomePage

Hey another thing you may wish to consider mentioning are the bugs in the NMOS version of the CPU.
One of them is with regard to the buggy IFF2->parity flag performance in the LD A,I and LD A,R instructions.
An error can occur when an INTACK runs near these instructions:
the parity flag will be showing 0 when it should have been 1.
A Zilog app. note is around somewhere talking about this.
It's a rather nasty bug for embeddedaapps... There are I think a few others.