Preliminary
Information
QUAD UART WITH RX/TX FIFO
COUNTERS,128-BYTE FIFO
XR16C854
DESCRIPTION
The XR16C854
*
1
(854) is a universal asynchronous receiver and transmitter (UART) with a dual foot print
interface compatible with the ST16C554D/654 and ST68C554/654. The 854 is an enhanced UART with 128 byte
FIFOs, Independent Transmit and Receive FIFO counter, automatic hardware/software flow control, and data
rates up to 1.5Mbps. Onboard status registers provide the user with error indications and operational status,
modem interface control. System interrupts may be tailored to meet user requirements. An internal loop-back
capability allows onboard diagnostics. The 854 is available in 64 pin TQFP, 68 pin PLCC, and 100 pin QFP
packages. The 64 pin package offers the 16 interface mode which is compatible with the industry standard
ST16C554. The 68 and 100 pin packages offer an additional 68 mode which allows easy integration with Motorola,
and other popular microprocessors. The XR16C854CV (64 pin) offers three state interrupt control while the
XR16C854DV provides constant active interrupt outputs. The 64 pin devices do not offer TXRDY/RXRDY outputs
or the default clock select option (CLKSEL). The 100 pin packages offer faster channel status access by providing
separate outputs for TXRDY and RXRDY, offer separate Infrared TX outputs and a musical instrument clock input
(MIDICLK). The 854 combines the package interface modes of the 16C554/654 and 68C554/654 series on a
single integrated chip.
FEATURES
•
Compatibility with the Industry Standard
ST16C554/654, ST68C554/654, TL16C554
•
1.5 Mbps transmit/receive operation (24MHz)
•
128 byte transmit and receive FIFO
•
Independent transmit and receive FIFO counter
•
Automatic software/hardware flow control
•
Programmable Xon/Xoff characters
•
Software selectable Baud Rate Generator pre-
scaleable clock rates of 1X, 4X.
•
Four selectable, and Programmable Transmit/
Receive FIFO interrupt trigger levels
•
Standard modem interface or infrared IrDA en-
coder/decoder interface
•
Software flow control turned off optionally by any
(Xon) RX character
•
Independent MIDI interface on 100 pin packages
•
100 pin packages offer internal register FIFO
monitoring and separate IrDA TX outputs
•
Sleep mode ( 200µA stand-by)
PLCC Package
INTSEL
-CDD
63
60
59
58
57
56
55
54
-CDA
GND
VCC
RXD
63
RXA
-RID
62
-RIA
D7
D6
D5
D4
D3
D2
D1
67
D0
66
68
65
-DSRA
-CTSA
-DTRA
VCC
-RTSA
INTA
-CSA
TXA
-IOW
TXB
-CSB
INTB
-RTSB
GND
-DTRB
-CTSB
-DSRB
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
-DSRD
-CTSD
-DTRD
GND
-RTSD
INTD
-CSD
TXD
-IOR
TXC
-CSC
INTC
-RTSC
VCC
-DTRC
-CTSC
-DSRC
XR16C854CJ
16 MODE
53
52
51
50
49
48
47
46
45
44
-CDB
RXB
RXC
-RIC
-RXRDY
CLKSEL
-TXRDY
RESET
16/-68
XTAL1
XTAL2
ORDERING INFORMATION
Part number
XR16C854CJ
XR16C854CV
XR16C854DCV
XR16C854CQ
68
64
64
100
Pins
PLCC
TQFP
TQFP
QFP
Package Operating temperature
0° C to + 70° C
0° C to + 70° C
0° C to + 70° C
0° C to + 70° C
Part number
XR16C854IJ
XR16C854IV
XR16C854DIV
XR16C854IQ
Note *1: Patent Pending
68
64
64
100
Pins
PLCC
TQFP
TQFP
QFP
Package Operating temperature
-40° C to + 85° C
-40° C to + 85° C
-40° C to + 85° C
-40° C to + 85° C
Rev. 1.00P
EXAR
Corporation, 48720 Kato Road, Fremont, CA 94538
•
(510) 668-7000
•
FAX (510) 668-7017
-CDC
A2
A1
A0
GND
-RIB
EXAR [ EXAR CORPORATION ]
