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CHAPTER 23 LOCAL BUS INTERFACE FUNCTIONS
User’s Manual U12697EJ3V0UM
Figure 23-5. Instruction Fetch from External Memory in External Memory Expansion Mode
(a) Setting 0 wait cycles (PW01, PW00 = 0, 0)
ASTB
RD
AD0 to AD7
A8 to A19
Lower address
Instruction code
Higher address
(b) Setting 1 wait cycle (PW01, PW00 = 0, 1)
ASTB
RD
AD0 to AD7
A8 to A19
Lower address
Instruction code
Higher address
Internal wait signal
(1 clock wait)
(c) Setting an external wait (PW01, PW00 = 1, 1)
ASTB
RD
AD0 to AD7
A8 to A19
Instruction code
Higher address
Lower address
WAIT