SM8954B
8-Bit Micro-controller
16KB Flash
& 1KB RAM embedded
Pin Description
40L
PDIP
44L
PLCC PQFP
44L
Symbol
I/O
Description
1
2
3
4
5
6
7
39
40
41
42
43
44
1
P4.2
I/O Bit 2 of port 4
1
2
3
4
5
P1.0/T2
P1.1/T2EX
P1.2/PWM0
P1.3/PWM1
P1.4
I/O Bit 0 of port 1 & Timer 2 external input clock
I/O Bit 1 of port 1 & Timer 2 capture trigger
I/O Bit 2 of port 1 & PWM Channel 0
I/O Bit 3 of port 1 & PWM Channel 1
I/O Bit 4 of port 1
6
P1.5
I/O Bit 5 of port 1
7
8
9
10
8
9
2
3
4
5
6
7
8
9
P1.6/SCL
P1.7/SDA
RESET
P3.0/RXD
P4.3
P3.1/TXD
P3.2/INT0
P3.3/INT1
P3.4/T0
P3.5/T1
P3.6/WR
P3.7/RD
XTAL2
I/O Bit 6 of port 1 & IIC SCL pin
I/O Bit 7 of port 1 & IIC SDA pin
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
I
Reset pin
I/O Bit 0 of port 3 & Serial interface channel receive data
I/O Bit 3 of port 4
I/O Bit 1 of port 3 & Serial interface channel Transmit data
I/O Bit 2 of port 3 & Interrupt 0
11
12
13
14
15
16
17
18
19
20
I/O Bit 3 of port 3 & Interrupt 1
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
I/O Bit 4 of port 3 & Timer 0 external input
I/O Bit 5 of port 3 & Timer 1 external input
I/O Bit 6 of port 3 & external memory write
I/O Bit 7 of port 3 & external memory read
I/O Crystal output
XTAL1
VSS
P4.0
I/O Crystal input
I
Ground
I/O Bit 0 of port 4
21
22
23
24
25
26
27
28
29
30
P2.0/A8
P2.1/A9
P2.2/A10
P2.3/A11
P2.4/A12
P2.5/A13
P2.6/A14
P2.7/A15
PSEN
I/O Bit 0 of port 2 & bit 8 of external memory address
I/O Bit 1 of port 2 & bit 9 of external memory address
I/O Bit 2 of port 2 & bit 10 of external memory address
I/O Bit 3 of port 2 & bit 11 of external memory address
I/O Bit 4 of port 2 & bit 12 of external memory address
I/O Bit 5 of port 2 & bit 13 of external memory address
I/O Bit 6 of port 2 & bit 14 of external memory address
I/O Bit 7 of port 2 & bit 15 of external memory address
O
O
program storage enable
address latch enable
ALE
P4.1
EA
I/O Bit 1 of port 4
external access
31
32
33
34
35
36
37
38
39
40
I
P0.7/AD7
P0.6/AD6
P0.5/AD5
P0.4/AD4
P0.3/AD3
P0.2/AD2
P0.1/AD1
P0.0/AD0
VDD
I/O Bit 7 of port 0 & data/address bit 7 of external memory
I/O Bit 6 of port 0 & data/address bit 6 of external memory
I/O Bit 5 of port 0 & data/address bit 5 of external memory
I/O Bit 4 of port 0 & data/address bit 4 of external memory
I/O Bit 3 of port 0 & data/address bit 3 of external memory
I/O Bit 2 of port 0 & data/address bit 2 of external memory
I/O Bit 1 of port 0 & data/address bit 1 of external memory
I/O Bit 0 of port 0 & data/address bit 0 of external memory
I
Power supply
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M083 Ver A SM8954B 3/7/2014
- 8 -
SYNCMOS [ SYNCMOS TECHNOLOGIES,INC ]
