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VRS51x550/560
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Pin Descriptions for QFP-44
TABLE 1: PIN DESCRIPTIONS FOR QFP-44/
QFP
- 44
Name
I/O
Function
1
P1.5
I/O
Bit 5 of Port 1
2
P1.6
I/O
Bit 6 of Port 1
3
P1.7
I/O
Bit 7 of Port 1
4
RES
I
Reset
RXD
I
Receive Data
5
P3.0
I/O
Bit 0 of Port 3
6
NC
-
No Connect
TXD
O
Transmit Data &
7
P3.1
I/O
Bit 1 of Port 3
#INT0
I
External Interrupt 0
8
P3.2
I/O
Bit 2 of Port 3
#INT1
I
External Interrupt 1
9
P3.3
I/O
Bit 3 of Port 3
T0
I
Timer 0
10
P3.4
I/O
Bit 4 of Port 3
T1
I
Timer 1 & 3
11
P3.5
I/O
Bit 5 of Port
#WR
O
Ext. Memory Write
12
P3.6
I/O
Bit 6 of Port 3
#RD
O
Ext. Memory Read
13
P3.7
I/O
Bit 7 of Port 3
14
XTAL2
O
Oscillator/Crystal Output
15
XTAL1
I
Oscillator/Crystal In
16
VSS
-
Ground
17
NC
-
No Connect
P2.0
I/O
Bit 0 of Port 2
18
A8
O
Bit 8 of External Memory Address
P2.1
I/O
Bit 1 of Port 2
19
A9
O
Bit 9 of External Memory Address
P2.2
I/O
Bit 2 of Port 2
20
A10
O
Bit 10 of External Memory Address
P2.3
I/O
Bit 3 of Port 2 &
21
A11
O
Bit 11 of External Memory Address
P2.4
I/O
Bit 4 of Port 2
22
A12
O
Bit 12 of External Memory Address
P2.5
I/O
Bit 5 of Port 2
23
A13
O
Bit 13 of External Memory Address
QFP
- 44
Name
I/O
Function
P2.6
I/O
Bit 6 of Port 2
24
A14
O
Bit 14 of External Memory Address
P2.7
I/O
Bit 7 of Port 2
25
A15
O
Bit 15 of External Memory Address
26
#PSEN
O
Program Store Enable
27
ALE
O
Address Latch Enable
28
NC
-
No Connect
29
#EA
I
External Access
P0.7
I/O
Bit 7 Of Port 0
30
AD7
I/O
Data/Address Bit 7 of External Memory
P0.6
I/O
Bit 6 of Port 0
31
AD6
I/O
Data/Address Bit 6 of External Memory
P0.5
I/O
Bit 5 of Port 0
32
AD5
I/O
Data/Address Bit 5 of External Memory
P0.4
I/O
Bit 4 of Port 0
33
AD4
I/O
Data/Address Bit 4 of External Memory
P0.3
I/O
Bit 3 Of Port 0
34
AD3
I/O
Data/Address Bit 3 of External Memory
P0.2
I/O
Bit 2 of Port 0
35
AD2
I/O
Data/Address Bit 2 of External Memory
P0. 1
I/O
Bit 1 of Port 0 & Data
36
AD1
I/O
Address Bit 1 of External Memory
P0.0
I/O
Bit 0 Of Port 0 & Data
37
AD0
I/O
Address Bit 0 of External Memory
38
VDD
-
VCC
39
NC
-
No Connect
T2
I
Timer 2 Clock Out
40
P1.0
I/O
Bit 0 of Port 1
T2EX
I
Timer 2 Control
41
P1.1
I/O
Bit 1 of Port 1
42
P1.2
I/O
Bit 2 of Port 1
43
P1.3
I/O
Bit 3 of Port 1
44
P1.4
I/O
Bit 4 of Port 1
1
44
11
12
22
23
33
34
VRS51x550/560
QFP-44
#RD/P3.7
#WR/P3.6
XTAL1
XTAL2
NC
VSS
P2.1/A9
P2.0/A8
P2.3/A11
P2.2/A10
P2.4/A12
P1.3
P1.4
T2EX/P1.1
P1.2
NC
T2/P1.0
P0.0/AD0
VDD
P0.2/AD2
P0.1/AD1
P0.3/AD3
35
36
37
38
39
40
41
42
43
21
20
19
18
17
16
15
14
13
32 31 30 29 28 27 26 25 24
2
3
4
5
6
7
8
9 10
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