527
DRACCR—DRAM Access Control Register
H'FED2
Bus Controller
Bit
Initial value
Read/Write
7
DRMI
0
R/W
6
—
0
R/W
5
TPC1
0
R/W
4
TPC0
0
R/W
3
—
0
R/W
2
—
0
R/W
1
RCD1
0
R/W
0
RCD0
0
R/W
RAS
-
CAS
Wait Control
0
Wait cycle not inserted between
RAS
assert cycle and
CAS
assert cycle
1
0
1
0
1
1-state wait cycle inserted between
RAS
assert cycle and
CAS
assert cycle
2-state wait cycle inserted between
RAS
assert cycle and
CAS
assert cycle
3-state wait cycle inserted between
RAS
assert cycle and
CAS
assert cycle
Precharge State Control
0
RAS
precharge cycle comprises 1 state
1
0
1
0
1
RAS
precharge cycle comprises 2 states
RAS
precharge cycle comprises 3 states
RAS
precharge cycle comprises 4 states
Idle Cycle Insertion
0
Idle cycle not inserted after DRAM space access
1
Idle cycle inserted after DRAM space access
Idle cycle insertion conditions, setting of number of states, etc.,
comply with settings of bits ICIS1, ICIS0, and IDLC in BCR register
Содержание H8S/2670
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