165
Accesses to on-chip spaces are as follows: On-chip supporting module spaces (area 5 when
address bit A27 is 1) are always 3-state access spaces, regardless of WCR, with no
WAIT
signal
sampling. Accesses to on-chip ROM (area 0 when MD2–MD0 are 010) and on-chip RAM (area 7
when address bit A27 is 0) are always performed in 1 state, regardless of WCR, with no
WAIT
signal sampling.
If the bus timing specifications (t
WTS
and t
WTH
) are not observed when the
WAIT
signal is input
in external space access, this will simply mean that
WAIT
signal assertion and negation will not
be detected, but will not result in misoperation. Note, however, that the inability to detect
WAIT
signal assertion may result in a problem with memory access due to insertion of an insufficient
number of waits.
Содержание HD6417032
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