7.2 Wait-State Control Register
The wait-state control register (WCR) is an 8-bit register that specifies the wait mode and the
number of wait states to be inserted. A reset initializes the WCR to specify the programmable
wait mode with three wait states. The WCR is not initialized in the software standby mode.
Bits 7 to 4—Reserved: These bits cannot be modified and are always read as “1.”
Bits 3 and 2—Wait Mode Select 1 and 0 (WMS1 and WMS0): These bits select the wait mode
as shown below.
Bits 1 and 0—Wait Count (WC1 and WC0): These bits specify the number of wait states to be
inserted.
Wait states are inserted only in bus cycles in which the CPU or DTC accesses an external address.
Bit 76543210
————WMS1 WMS0 WC1 WC0
Initial value 11110011
Read/Write ————R/WR/WR/WR/W
Bit 3 Bit 2
WMS1 WMS0 Description
0 0 Programmable wait mode (Initial value)
0 1 No wait states are inserted, regardless of the wait count.
1 0 Pin wait mode
1 1 Pin auto-wait mode
Bit 1 Bit 0
WC1 WC0 Description
0 0 No wait states are inserted, except in pin wait mode.
0 1 1 Wait state in inserted.
1 0 2 Wait states are inserted.
1 1 3 Wait states are inserted. (Initial value)
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