ST16C552
ST16C552A
DUAL UART WITH 16-BYTE FIFO AND
PARALLEL PRINTER PORT
December 2003
DESCRIPTION
The ST16C552/ST16C552A (552/552A) is a dual universal asynchronous receiver and transmitter (UART) with
an added bi-directional parallel port that is directly compatible with a CENTRONICS type printer. The parallel port
is designed such that the user can configure it as general purpose I/O interface, or for connection to other printer
devices. The 552/552A provides enhanced UART functions with 16 byte FIFO’s, a modem control interface, and
data rates up to 1.5Mbps. Onboard status registers provide the user with error indications and operational status.
The system interrupts and control may be tailored to meet user requirements. An internal loop-back capability
allows onboard diagnostics. A programmable baud rate generator is provided to select transmit and receive clock
rates from 50 bps to 1.5 Mbps. The 552/552A is available in a 68 pin PLCC package. The 552/552A is compatible
with the 16C450 and 16C550. The difference between the ST16C552 and ST16C552A is the logic state of the
printer port, INTP interrupt. The INTP interrupt is active high (logic 1) on the ST16C552 whereas INTP is active
low (logic 0) on the ST16C552A part when the interrupt latch mode is selected. The 552/552A is fabricated in an
advanced CMOS process with power down mode to reduce the power consumption. The 552A does not support
the power down mode.
FEATURES
-RXRDYA
PLCC Package
-RXRDYB
61
60
59
58
57
56
55
54
ERROR
63
-DSRB
BIDEN
-BUSY
SLCT
-CDB
-CSB
GND
GND
VCC
ACK
RXB
62
-RIB
CLK
Added features in device revision "F" and newer:
•
5V Tolerant Inputs
•
Pin to pin and functional compatible to ST16C452/
452PS, TL16C552
•
2.97 to 5.5 volt operation
•
Software compatible with INS8250, NS16C550
•
1.5 Mbps transmit/receive operation (24MHz)
•
16 byte transmit FIFO
•
16 byte receive FIFO with error flags
•
Independent transmit and receive control
•
Modem and printer status registers
•
UART port and printer port Bi-directional
•
Printer port direction set by single control bit or 8 bit
pattern (AA/55)
•
Modem control signals (-CTS, -RTS, -DSR, -DTR,
-RI, -CD)
•
Programmable character lengths (5, 6, 7, 8)
•
Even, odd, or no parity bit generation and detection
•
TTL compatible inputs, outputs
•
Power down mode
68
67
PE
66
65
TXB
-DTRB
-RTSB
-CTSB
D0
D1
D2
D3
D4
D5
D6
D7
-TXRDYA
VCC
-RTSA
-DTRA
TXA
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
64
9
8
7
6
5
4
3
2
1
INTB
INTP
-SLCTIN
INIT
-AUTOFDXT
-STROBE
GND
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
INTA
RDOUT
ST16C552CJ68
ST16C552ACJ68
53
52
51
50
49
48
47
46
45
44
-IOW
A2
A1
A0
-RESET
-CTSA
-CSA
-CSP
RXA
-RIA
-TXRDYB
-DSRA
-CDA
GND
VCC
-IOR
ORDERING INFORMATION
Part number
Pins
Package
Operating temperature
Device Status
ST16C552CJ68
ST16C552ACJ68
ST16C552IJ68
ST16C552AIJ68
68
68
68
68
PLCC
PLCC
PLCC
PLCC
0° C to + 70° C
0° C to + 70° C
-40° C to + 85° C
-40° C to + 85° C
Active
Active
Active
Active
Rev. 3.40
EXAR
Corporation, 48720 Kato Road, Fremont, CA 94538
•
(510) 668-7000
•
FAX (510) 668-7017
INTSEL
EXAR [ EXAR CORPORATION ]
