XR16C2552 Datasheet, PDF (4/36 Pages) Exar Corporation – 2.97V TO 5.5V DUAL UART WITH 16-BYTE FIFO

XR16C2552
2.97V TO 5.5V DUAL UART WITH 16-BYTE FIFO
xr
REV. 1.0.0
Pin Description
NAME
44-PLCC
PIN #
TYPE
DESCRIPTION
MFA#
35
O Multi-Function Output Channel A. This output pin can function as the OP2A#, BAUD-
OUTA#, or RXRDYA# pin. One of these output signal functions can be selected by
the user programmable bits 1-2 of the Alternate Function Register (AFR). These sig-
nal functions are described as follows:
1) OP2A# - When OP2A# (active low) is selected, the MF# pin is a logic 0 when MCR
bit-3 is set to a logic 1 (see MCR bit-3). MCR bit-3 defaults to a logic 0 condition after
a reset or power-up.
2) BAUDOUTA# - When BAUDOUTA# function is selected, the 16X Baud rate clock
output is available at this pin.
3) RXRDYA# - RXRDYA# (active low) is intended for monitoring DMA data transfers.
See Table 2 for more details.
If it is not used, leave it unconnected.
MFB#
19
O Multi-Function Output ChannelB. This output pin can function as the OP2B#, BAUD-
OUTB#, or RXRDYB# pin. One of these output signal functions can be selected by
the user programmable bits 1-2 of the Alternate Function Register (AFR). These sig-
nal functions are described as follows:
1) OP2B# - When OP2B# (active low) is selected, the MF# pin is a logic 0 when MCR
bit-3 is set to a logic 1 (see MCR bit-3). MCR bit-3 defaults to a logic 0 condition after
a reset or power-up.
2) BAUDOUTB# - When BAUDOUTB# function is selected, the 16X Baud rate clock
output is available at this pin.
3) RXRDYB# - RXRDYB# (active low) is intended for monitoring DMA data transfers.
See Table 2 for more details.
TXA
38
RXA
39
RTSA#
36
CTSA#
40
DTRA#
37
DSRA#
41
CDA#
42
If it is not used, leave it unconnected.
O UART channel A Transmit Data. If it is not used, leave it unconnected.
I UART channel A Receive Data. Normal receive data input must idle at logic 1 condi-
tion. If it 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 output. If it is not
used, leave it unconnected.
I UART channel A Clear-to-Send (active low) or general purpose input. This input
should be connected to VCC when not used. This input has no effect on the UART.
O UART channel A Data-Terminal-Ready (active low) or general purpose output. If it 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. This input has no effect on the UART.
I UART channel A Carrier-Detect (active low) or general purpose input. This input
should be connected to VCC when not used. This input has no effect on the UART.
4