80C31 Datasheet, PDF (18/30 Pages) NXP Semiconductors – CMOS single-chip 8-bit microcontrollers

Philips Semiconductors
CMOS single-chip 8-bit microcontrollers
Product specification
80C31/80C51/87C51
ALE
PSEN
t_WHLH
WR
PORT 0
PORT 2
INSTRUCTION
ALE
CLOCK
OUTPUT DATA
WRITE TO SBUF
INPUT DATA
CLEAR RI
t_LLWL
t_WLWH
t_AVLL
t_LLAX
A0–A7
FROM RI OR DPL
t_AVWL
t_QVWX
DATA OUT
P2.0–P2.7 OR A8–A15 FROM DPH
t_WHQX
A0–A7 FROM PCL
A0–A15 FROM PCH
Figure 3. External Data Memory Write Cycle
0
1
2
3
4
5
6
7
INSTR IN
SU00008
8
t_XLXL
t_QVXH
t_XHQX
0
t_XHDV
VALID
1
2
t_XHDX
VALID
VALID
3
VALID
4
VALID
Figure 4. Shift Register Mode Timing
5
VALID
6
VALID
7
SET TI
VALID
SET RI
SU00027
V_CC–0.5
0.45V
0.7V_CC
0.2V_CC–0.1
t_CHCL
t_CLCX
t_CHCX
t_CLCH
t_CLCL
Figure 5. External Clock Drive
SU00009
1996 Aug 16
18