ST16C452
ST16C452PS
DUAL UART WITH PARALLEL
PRINTER PORT
March2004
DESCRIPTION
The ST16C452/ST16C452PS (452/452PS) 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 452/452PS provides enhanced UART functions, a modem control interface, and data rates
upto1.5Mbps. Onboardstatusregistersprovidetheuserwitherrorindicationsandoperationalstatus. Thesystem
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 452/452PS is available in a 68 pin PLCC package. The 452/452PS is compatible with the
16C450. The 452 is available in two versions, the ST16C452 and the ST16C452PS. The ST16C452 provides
single hardware pin to control the printer port data direction while the 452PS provides an additionally software
control bit to control the printer port data direction to become compatible PS/2 operating system.
The 452/452PS is fabricated in an advanced CMOS process with low power consumption.
PLCC Package
FEATURES
Addedfeaturesindeviceswithtopmarkdatecodeof
"F2 YYWW" and newer:
TXB 10
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
INTB
-DTRB 11
INTP
• 5VTolerantInputs
• Pin to pin and functional compatible to TL16C452
• 2.97 to 5.5 volt operation
• SoftwarecompatiblewithST16C450,NS16C450
• 1.5Mbpstransmit/receiveoperation(24MHz)
• Independent transmitandreceivecontrol
• Modem and printer status registers
• UARTportandprinterportBi-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, ornoparitybitgenerationanddetection
• Internal loop-back diagnostics
12
13
-RTSB
-CTSB
-SLCTIN
INIT
D0 14
D1 15
D2 16
-AUTOFDXT
-STROBE
GND
17
18
D3
D4
PD0
ST16C452CJ68
ST16C452CJ68PS
PD1
D5 19
D6 20
D7 21
PD2
PD3
PD4
22
23
24
N.C.
VCC
PD5
PD6
PD7
-RTSA
-DTRA 25
TXA 26
INTA
RDOUT
• TTL compatible inputs, outputs
• LowPower
ORDERING INFORMATION
Part number
Package
Operating temperature Device Status
ST16C452CJ68
ST16C452CJ68PS
ST16C452IJ68
ST16C452IJ68PS
68-Lead PLCC
68-Lead PLCC
68-Lead PLCC
68-Lead 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.3.20
EXAR Corporation, 48720 Kato Road, Fremont, CA 94538 • (510) 668-7000 • FAX (510) 668-7017