W79E825A Datasheet, PDF (57/127 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E825A/824A/823B/822B Data Sheet
CPU CLK
ALE
PSEN
AD<7:0>
Address<15:0>
Instruction Fetch
C1
C2
C3
C4
PC
OP-CODE
Address A15-8
Operand Fetch
C1
C2
C3
C4
PC+1
OPERAND
Address A15-8
Figure 9-2: Two Cycles Instruction Timing
CPU CLK
ALE
Instruction Fetch
Operand Fetch
Operand Fetch
C1 C2 C3 C4 C1
C2 C3 C4 C1
C2 C3 C4
PSEN
AD<7:0>
A7-0
OP-CODE
A7-0 OPERAND
A7-0 OPERAND
Address<15:0>
Address A15-8
Address A15-8
Address A15-8
Figure 9-3: Three Cycles Instruction Timing
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Publication Release Date: February 21, 2008
Revision A9