XR16C2850IJ-F Datasheet, PDF (4/51 Pages) Exar Corporation – 2.97V TO 5.5V DUAL UART WITH 128-BYTE FIFOS

XR16C2850
2.97V TO 5.5V DUAL UART WITH 128-BYTE FIFOS
xr
REV. 2.1.3
NAME
RXRDYB#
44-PLCC
PIN #
23
48-TQFP
PIN #
18
TYPE
DESCRIPTION
O _{UART channel B Receiver Ready (active low). This output provides the}
RX FIFO/RHR status for receive channel B. See Table 2. If this output
is not used, leave it unconnected.
MODEM OR SERIAL I/O INTERFACE
TXA
13
7
RXA
11
5
RTSA#
36
33
CTSA#
40
38
DTRA#
37
34
DSRA#
41
39
CDA#
42
40
RIA#
43
41
OP2A#
35
32
TXB
14
8
O _{UART channel A Transmit Data or infrared encoder data. Standard}
transmit and receive interface is enabled when MCR[6] = 0. In this
mode, the TX signal will be HIGH during reset or idle (no data). Infrared
IrDA transmit and receive interface is enabled when MCR[6] = 1. In the
Infrared mode, the inactive state (no data) for the Infrared encoder/
decoder interface isLOW. If this output is not used, leave it uncon-
nected.
I _{UART channel A Receive Data or infrared receive data. Normal receive}
data input must idle HIGH. The infrared receiver pulses typically idles
LOW but can be inverted by software control prior going in to the
decoder, see MCR[6] and FCTR[2]. If this pin is not used, tie it to VCC
or pull it high via a 100k ohm resistor.
O _{UART channel A Request-to-Send (active low) or general purpose out-}
put. This output must be asserted prior to using auto RTS flow control,
see EFR[6], MCR[1], FCTR[1:0], EMSR[5:4] and IER[6]. For auto
RS485 half-duplex direction control, see FCTR[3]. If this output is not
used, leave it unconnected.
I _{UART channel A Clear-to-Send (active low) or general purpose input.}
It can be used for auto CTS flow control, see EFR[7], and IER[7]. This
input should be connected to VCC when not used.
O _{UART channel A Data-Terminal-Ready (active low) or general purpose}
output. If this output is not used, leave it unconnected.
I _{UART channel A Data-Set-Ready (active low) or general purpose input.}
This input should be connected to VCC when not used.
I _{UART channel A Carrier-Detect (active low) or general purpose input.}
This input should be connected to VCC when not used.
I _{UART channel A Ring-Indicator (active low) or general purpose input.}
This input should be connected to VCC when not used.
O _{Output Port 2 Channel A - The output state is defined by the user and}
through the software setting of MCR[3]. INTA is set to the active mode
and OP2A# output is LOW when MCR[3] is set to a logic 1. INTA is set
to the three state mode and OP2A# is HIGH when MCR[3] is set to a
logic 0. See MCR[3]. This output can only be used as a general pur-
pose output when interrupts are not used, otherwise it will disturb the
INTA output functionality. If this output is not used, leave it uncon-
nected.
O _{UART channel B Transmit Data or infrared encoder data. Standard}
transmit and receive interface is enabled when MCR[6] = 0. In this
mode, the TX signal will be HIGH during reset or idle (no data). Infrared
IrDA transmit and receive interface is enabled when MCR[6] = 1. In the
Infrared mode, the inactive state (no data) for the Infrared encoder/
decoder interface is LOW. If this output is not used, leave it uncon-
nected.
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