Hitachi SH7032 - Wait State Control Register 3 (WCR3)

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Table 8.6 Single-Mode DMA Memory Write Cycle States (External Memory Space)
Single-Mode DMA Memory Write Cycle States
(External Memory Space)
Bits 15–8:
DWW7–DWW0
WAIT Pin Input
Signal
External Memory
Space DRAM Space
Multiplexed
I/O
0 Not sampled during
single-mode DMA
memory write 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 state
from WAIT
1 Sampled during
single-mode DMA
memory write cycle
(Initial value)
Areas 1, 3–5, 7: 2 states
+ wait state 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.
8.2.4 Wait State Control Register 3 (WCR3)
Wait state control register 3 is a 16-bit read/write register that controls WAIT pin pull-up and the
insertion of long wait states. WCR3 is initialized to H'F800 by a power-on reset. It is not
initialized by a manual reset or in standby mode.
Bit: 15 14 13 12 11 10 9 8
Bit name: WPU A02LW1 A02LW0 A6LW1 A6LW0 — — —
Initial value: 1 1 1 1 1 0 0 0
R/W: R/W R/W R/W R/W R/W — — —
Bit: 7 6 5 4 3 2 1 0
Bit name: — — — — — — — —
Initial value: 0 0 0 0 0 0 0 0
R/W: — — — — — — — —
• Bit 15 (Wait Pin Pull-Up Control (WPU)): WPU controls whether the WAIT pin is pulled up
or not. When cleared to 0, the pin is not pulled up; when set to 1, it is pulled up.
Bit 15: WPU Description
0 WAIT pin is not pulled up
1 WAIT pin is pulled up (Initial value)