IS80C51 Datasheet, PDF (41/43 Pages) Integrated Silicon Solution, Inc – CMOS SINGLE CHIP 8-BIT MICROCONTROLLER

IS80C51
IS80C31
ISSI ^®
ALE
PSEN
WR
PORT 0
PORT 2
tWHLH
tLLWL
tWLWH
tAVLL
tLLAX
A7-A0 FROM RI OR DPL
tAVWL
tQVWX
DATA OUT
A15-A8 FROM DPH
tWHQX
A7-A0 FROM PCL
INSTR IN
A15-A8 FROM PCH
Figure 31. External Data Memory Write Cycle
INSTRUCTION
ALE
CLOCK
DATAOUT
DATAIN
0
1
2
3
4
5
6
7
8
tXLXL
tQVXH
0
tXHQX
1
tXHDV
VALID
VALID
2
tXHDX
VALID
3
VALID
4
VALID
5
VALID
Figure 32. Shift Register Mode Timing Waveform
6
VALID
7
SET TI
VALID
SET RI
Integrated Silicon Solution, Inc. — 1-800-379-4774
41
MC003-1D
11/19/98