
CHAPTER 5 BUS CONTROL FUNCTION
User’s Manual U15905EJ2V1UD
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5.6.3
Relationship between programmable wait and external wait
Wait cycles are inserted as the result of an OR operation between the wait cycles specified by the set value of the
programmable wait and the wait cycles controlled by the WAIT pin.
Wait control
Programmable wait
Wait via WAIT pin
For example, if the timing of the programmable wait and the WAIT pin signal is as illustrated below, three wait
states will be inserted in the bus cycle.
Figure 5-3. Example of Wait Insertion
(a) In separate bus mode
T1
TW
T2
CLKOUT
WAIT pin
Wait via WAIT pin
Programmable wait
Wait control
Remark
The circles indicate the sampling timing.
(b) In multiplexed bus mode
CLKOUT
T1
T2
TW
T3
WAIT pin
Wait by WAIT pin
Programmable wait
Wait control
Remark
The circles indicate the sampling timing.