Memotech Limited MTX 500, Service Manual

Page: 13 / 78

9
RFSH.
Refresh (output, active Low). RFSH, together with
MREQ, indicates that the lower seven bits of the
system's address bus can be used as a refresh
address to the system's dynamic memories.
WAIT.
Wait (input, active Low). WAIT indicates to the
CPU that the addressed memory or I/O devices are
not ready for a data transfer. The CPU continues
to enter a Wait state as long as this signal is
active. Extended WAIT periods can prevent the CPU
from refreshing dynamic memory properly.
WR.
Write (output, active Low, 3-state). WR indicates
that the CPU data bus holds valid data to be
stored at the addressed memory or I/O location.
MTX Service Manual