XR16C872 Datasheet, PDF (4/60 Pages) Exar Corporation – DUAL UART WITH 1284 PARALLEL PORT AND PLUG-AND-PLAY CONTROLLER

XR16C872
DISCONTINUED
To ISA Bus
D0-D7
A0-A10
AEN
IOR#
IOW#
IOCHRDY
IRQ3
IRQ4
IRQ5
IRQ7
DREQ3
DACK3#
TC
MAN#
GND
S1
Hardwired _S2
or
S3
Jumpers
S4
S5
ISA Bus
Interface
Controller
Address
Decoder for
COM1-4 and
LP1-2
UART Channel A
Transmit
FIFO
(128
bytes)
Transmit
Shift
Register
IrDA v1.0
Encoder
UART
Control
Registers
Receive
FIFO
(128
bytes)
Receive
Shift
Register
IrDA v1.0
Decoder
Baud Rate Gen.
Modem
Interface
UART Channel B
(same as channel A block)
RESET
XTAL1
(22.1184 MHz)
XTAL2
Osc./
Buffer
7.3728 MHz
Divide
by 3
1284 Bi-directional
Parallel Port Controller with
Level II Electrical Interface
TXA
RXA
To Serial Port A
Transceivers
DTRA#
RTSA#
DSRA#
CTSA#
CDA#
RIA#
TXB,
RXB,
DTR#,
RTS#, etc.
To Serial Port B
Transceivers
PD0-PD7
INIT#
STROBE#
SELCTIN#
AUTOFD#
PDIR
PE
SELECT
BUSY
ACK#
ERR#
To Parallel
Printer Port
Figure 3, Funtional Block Diagram with Manual Configuration Interface.
Rev. 1.00
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