21 Apr
2016
21 Apr
'16
9:18 p.m.
On 04/21/2016 12:36 PM, Eric Smith wrote:
A friend building a Z80 system asked me about whether
the Z80 /WAIT
signal has any effect during machine cycles that aren't
memory/IO/intack cycles (i.e., neither /MREQ and /IORQ asserted). The
user manual only describes the use of /WAIT for adding wait states, so
I expect it probably only affects mem/IO/intack cycles, but I can't
find anything definitive in the user manual.
Oh, boy! I ought to know this one, but really don't. I
never tried to use it except on some kind of data cycle.
It could, possibly, depend on what implementation of the
Z-80 you are using. I built some battery-powered stuff
using a Harris Z-80 clone that was all CMOS. Some timings
were a bit different from a Zilog Z-80.
Jon