> Incidentally, what are the 5 cycles for an LDIR? It uses the same technique as used by relative jumps to add a value of -2 to PC.
>so is it really the case that the z80 reads the (erroneous) next instruction before doing PC-=2 (as > one source on the web suggested)? I think that suggestion comes from a TI 83/87 related sources. As I understand it, those calculators use a custom Z80 that uses prefetch. Ordinary Z80s do not have prefetch. Edwin
