Z80 its refresh pin

[srkh28@gmail.com]

Hi Folks,


Im putting together a Z80 clone card for the Apple II (softcard copy),
but have have come across some unusual behaviour of my Z80 that im not
familiar with (its a NEC D780C) - and that is, it asserts its refresh
pin low (28), and keeps it there?? (right after reset - I need it high
to boot). Ive read the data sheet, and acordingly this refresh is a
state machine thats controlled by the R register that simply times its
self from the clock pin (6)

Any idea's on why this could be happening??


thanks,
Steve