upd70208h Renesas Electronics Corporation., upd70208h Datasheet - Page 27

• Manufacturer Part Number: upd70208h
• Description: V40hltm, V50hltm 16/8, 16-bit Microprocessor
• Manufacturer: Renesas Electronics Corporation.

7. WCU (WAIT CONTROL UNIT)
bus cycle.
7.1
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The WCU has the function of automatically inserting a wait state (TW) of 0 to 3 clock cycles in a CPU, DMAU or REFU
Automatic setting of 0 to 3 waits for a CPU memory bus cycle
1M-byte memory space can be divided into 5
64K-byte I/O space can be divided into 3
Automatic setting of 0 to 3 waits for an external I/O cycle
Automatic setting of 0 to 3 waits for a DMA cycle
Automatic setting of 0 to 3 waits for a refresh cycle
Same as V40 and V50 directly after a reset (memory space divided into 3, no division of I/O space)
Remark The division specification and the size of each block are set by means of a system I/O area register.
FEATURES
1 M-Byte
Memory Area
FFFFFH
00000H
Figure 7-1. Example of Memory Space Division
Upper Memory Block
Middle Memory Block
Lower Memory Block
Data Sheet U13225EJ4V0DS00
Upper Sub
Memory Block
Lower Sub
Memory Block
PD70208H, 70216H
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