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VMX51C900
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Pin Descriptions for QFP-44
TABLE 2: PIN DESCRIPTIONS FOR QFP-44
PLCC
- 44
Name
I/O
Function
PWMB
O
PWM Channel B
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
P4.3
I/O
Bit 3 of Port 4
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
ADCIN0
Ain
ADC input 0
T0
I
Timer 0
10
P3.4
I/O
Bit 4 of Port 3
ADCIN1
Ain
ADC input 1
T1
I
Timer 1 & 3
11
P3.5
I/O
Bit 5 of Port
ADCIN2
Ain
ADC input 2
#WR
O
Ext. Memory Write
12
P3.6
I/O
Bit 6 of Port 3
ADCIN3
Ain
ADC input 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
P4.0
I/O
Bit 0 of Port 4
LCDCOM0
-
LCD Driver Common 0
P2.0
I/O
Bit 0 of Port 2
18
A8
O
Bit 8 of Ext. Memory Address
LCDCOM1
-
LCD Driver Common 1
P2.1
I/O
Bit 1 of Port 2
19
A9
O
Bit 9 of Ext. Memory Address
LCDCOM2
-
LCD Driver Common 2
P2.2
I/O
Bit 2 of Port 2
20
A10
O
Bit 10 of Ext. Memory Address
LCDCOM3
-
LCD Driver Common 3
P2.3
I/O
Bit 3 of Port 2 &
21
A11
O
Bit 11 of Ext. Memory Address
LCDSEG0
-
LCD Segment 0
P2.4
I/O
Bit 4 of Port 2
22
A12
O
Bit 12 of Ext. Memory Address
LCDSEG1
-
LCD Segment 1
P2.5
I/O
Bit 5 of Port 2
23
A13
O
Bit 13 of External Memory Address
LCDSEG2
-
LCD Segment 2
P2.6
I/O
Bit 6 of Port 2
24
A14
O
Bit 14 of External Memory Address
LCDSEG3
-
LCD Segment 3
P2.7
I/O
Bit 7 of Port 2
25
A15
O
Bit 15 of External Memory Address
LCDSEG4
-
LCD Segment 4
26
#PSEN
O
Program Store Enable
LCDSEG5
-
LCD Segment 5
27
ALE
O
Address Latch Enable
PLCC
- 44
Name
I/O
Function
28
P4.1
I/O
Bit 1 of Port 4
29
#EA
I
External Access
LCDSEG6
-
LCD Segment 6
P0.7
I/O
Bit 7 Of Port 0
30
AD7
I/O
Data/Address Bit 7 of Ext. Memory
LCDSEG7
-
LCD Segment 7
P0.6
I/O
Bit 6 of Port 0
31
AD6
I/O
Data/Address Bit 6 of Ext. Memory
LCDSEG8
-
LCD Segment 8
P0.5
I/O
Bit 5 of Port 0
32
AD5
I/O
Data/Address Bit 5 of Ext. Memory
LCDSEG9
-
LCD Segment 9
P0.4
I/O
Bit 4 of Port 0
33
AD4
I/O
Data/Address Bit 4 of Ext. Memory
LCDSEG10
-
LCD Segment 10
P0.3
I/O
Bit 3 Of Port 0
34
AD3
I/O
Data/Address Bit 3 of Ext. Memory
LCDSEG11
-
LCD Segment 11
P0.2
I/O
Bit 2 of Port 0
35
AD2
I/O
Data/Address Bit 2 of Ext. Memory
LCDSEG12
-
LCD Segment 12
P0. 1
I/O
Bit 1 of Port 0 & Data
36
AD1
I/O
Address Bit 1 of Ext. Memory
LCDSEG13
-
LCD Segment 13
P0.0
I/O
Bit 0 Of Port 0 & Data
37
AD0
I/O
Address Bit 0 of Ext. Memory
38
VDD
-
5V supply
39
P4.2
I/O
Bit 2 of Port 4
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
P1.2
I/O
Bit 2 of Port 1
42
PWMA
O
PWM Channel A
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
VMX51C900
QFP-44
P3.7/#RD/ADCIN3
P3.6/#WR/ADCIN2
XTAL1
XTAL2
P4.0
VSS
P2.1/A9/LCDCOM1
P2.0/A8/LCDCOM0
P2.3/A11/LCDCOM3
P2.2/A10/LCDCOM2
P2.4/A12/LCDSEG0
P1.3
P1.4
T2EX/P1.1
PWMA/P1.2
P4.2
PWM0/T2/P1.0
LCDSEG13/AD0/P0.0
VDD
LCDSEG11/AD2/P0.2
LCDSEG12/AD1/P0.1
LCDSEG10/AD3/P0.3
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