FIGURE 2. PIN OUT ASSIGNMENT
48
47
46
45
44
43
42
41
40
39
38
37
1
2
3
4
5
6
7
8
9
10
11
12
36
35
34
33
32
31
30
29
28
27
26
25
13
14
15
16
17
18
19
20
21
22
23
24
D5
D6
D7
RXB
RXA
TXRDYB#
TXA
TXB
OP2B#
CSA#
CSB#
NC
XT
AL1
XT
AL2
IOW
#
CDB#
GND
RXRDY
B#
IOR
#
DS
RB#
RIB#
RT
S
B
#
CT
S
B
#
NC
RESET
DTRB#
DTRA#
RTSA#
OP2A#
RXRDYA#
INTA
INTB
A0
A1
A2
NC
D4
D3
D2
D1
D0
T
X
RDYA#
VC
C
RI
A#
CDA#
DSRA#
CT
SA#
NC
ST16C2550
48-pin TQFP
6
5
4
3
2
1
44
43
42
41
40
7
8
9
10
11
12
13
14
15
16
17
39
38
37
36
35
34
33
32
31
30
29
18
19
20
21
22
23
24
25
26
27
28
D5
D6
D7
RXB
RXA
TXRDYB#
TXA
TXB
OP2B#
CSA#
CSB#
RESET
DTRB#
DTRA#
RTSA#
OP2A#
RXRDYA#
INTA
INTB
A0
A1
A2
XT
AL
1
XT
AL
2
IO
W
#
CD
B#
GN
D
RXR
D
YB
#
IO
R
#
DS
R
B
#
RI
B
#
RT
SB
#
CT
SB
#
D4
D3
D2
D1
D0
TX
R
D
Y
A
#
VC
C
RI
A#
CD
A#
DS
RA
#
CT
SA
#
ST16C2550
44-pin PLCC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
D0
D1
D2
D3
D4
D5
D6
D7
RXB
RXA
TXA
TXB
OP2B#
CSA#
CSB#
XTAL1
XTAL2
IOW#
CDB#
GND
VCC
RIA#
CDA#
DSRA#
CTSA#
RESET
DTRB#
DTRA#
RTSA#
OP2A#
INTA
INTB
A0
A1
A2
CTSB#
RTSB#
RIB#
DSRB#
IOR#
S
T
16
C
25
5
0C
P
4
0
ST16C2550
2
2.97V TO 5.5V DUART WITH 16-BYTE FIFO
REV. 4.4.1