0 signal summary, Table 1. 8xc251tx signal summary – Intel 8xC251TB User Manual
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8xC251Tx Hardware Description
2
2.0 SIGNAL SUMMARY
Table 1. 8xC251Tx Signal Summary
Address & Data
Input/Output
Name
PLCC
DIP
Name
PLCC
DIP
AD0/P0.0
43
39
P1.0/T2
2
1
AD1/P0.1
42
38
P1.1/T2EX
3
2
AD2/P0.2
41
37
P1.2/EC/RXD1
4
3
AD3/P0.3
40
36
P1.3/CEX0/TXD1
5
4
AD4/P0.4
39
35
P1.4/CEX1
6
5
AD5/P0.5
38
34
P1.5/CEX2
7
6
AD6/P0.6
37
33
P1.6/CEX3/WAIT#
8
7
AD7/P0.7
36
32
P1.7/CEX4/A17/WCLK
9
8
A8/P2.0
24
21
P3.0/RXD
11
10
A9/P2.1
25
22
P3.1/TXD
13
11
A10/P2.2
26
23
P3.4/T0
16
14
A11/P2.3
27
24
P3.51/T1
17
15
A12/P2.4
28
25
A13/P2.5
29
26
Power & Ground
A14/P2.6
30
27
Name
PLCC
DIP
A15P2.7
31
28
V
CC
44
40
P3.7/RD#/A16
19
17
V
CC2
12
P1.7/CEX4/A17/WCLK
9
8
V
SS
22
20
V
SS1
1
Processor Control
V
SS2
23,24
Name
PLCC
DIP
P3.2/INT0#
14
12
Bus Control & Status
P3.3/INT1#
15
13
Name
PLCC
DIP
EA#
35
31
P3.6/WR#
18
16
RST
10
9
P3.7/RD#/A16
19
17
XTAL1
21
18
ALE
33
30
XTAL2
20
19
PSEN#
32
29
NOTE:
Pins in this font indicate functions associated with the second serial I/O port.