102 HITACHI
Table 8.4
Single-Mode DMA Memory Read Cycle States (External Memory Space)
Description
Single-Mode DMA Memory Read Cycle States
(External Memory Space)
Bits 15–8:
DRW7–DRW0
WAIT
Pin Input
Signal
External Memory
Space
DRAM Space
Multiplexed
I/O
0
Not sampled during
single-mode DMA
memory read cycle*
Areas 1, 3–5,7: 1 state,
fixed
Areas 0, 2, 6: 1 state +
long wait state
Column address
cycle: 1 state,
fixed (short
pitch)
4 states +
wait states
from
WAIT
1
Sampled during
single-mode DMA
memory read cycle
(initial value)
Areas 1, 3–5, 7: 2 states
+ wait states from
WAIT
Areas 0, 2, 6: 1 state +
long wait state + Wait
state from
WAIT
Column address
cycle: 2 states +
wait state from
WAIT
(long
pitch)
Note:
Sampled in the address/data multiplexed I/O space.
Bits 7–0 (single-mode DMA memory write wait state control (DWW7–DWW0)): DWW7–
DWW0 determine the number of states in single-mode DMA memory write cycles for each
area and whether or not to sample the
WAIT
signal. Bits DWW7–DWW0 correspond to areas
7–0, respectively. If a bit is cleared to 0, the
WAIT
signal is not sampled during the single-
mode DMA memory write cycle for the corresponding area. If it is set to 1, sampling takes
place.
The number of states for areas accesses based on bit settings are the same as indicated for
single-mode DMA memory read cycles. See bits 15–8, wait state control during single-mode
DMA memory transfer (DRW7–DRW0), for details.
Table 8.5 summarizes single-mode DMA memory write cycle state information.