XR18W750 Datasheet, PDF (4/44 Pages) Exar Corporation – WIRELESS UART CONTROLLER

XR18W750
WIRELESS UART CONTROLLER
Pin Description
REV. 1.0.0
NAME
RTS#
CTS#
DTR#
DSR#
CD#
RI#
48-QFN
PIN #
41
39
38
42
37
40
TYPE
DESCRIPTION
O _{UART Request-to-Send (active low) or general purpose output. 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].
I _{UART 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 Data-Terminal-Ready (active low) or general purpose output. If it is not}
used, leave it unconnected.
I _{UART 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 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.
I _{UART Ring-Indicator (active low) or general purpose input. This input should be}
connected to VCC when not used. This input has no effect on the UART.
RF TRANSCEIVER INTERFACE SIGNALS
MODEM_RESET
1
O _{Reset output to the RF transceiver.}
RF_IRQ#
8
I _{Interrupt input from RF transceiver.}
SDA
11
I/O _I2_{C Serial Data Line.}
SCL
12
I/O _I2_{C Serial Clock Line. The I}2_{C clock frequency can be up to 400 KHz.}
RF_DO
9
O _{Data out to RF transceiver.}
RF_DI
10
I _{Data in from RF transceiver.}
EN_DIDO
36
I _{Enable RF_DI and RF_DO (active high) for sending data to and from RF trans-}
ceiver. If I²C bus is used for this purpose, this input should be connected to
GND.
ANCILLARY SIGNALS
S/P#
46
I _{Serial or Parallel Mode select. If this pin is HIGH, then the serial interface will be}
enabled. If this pin is LOW, then the parallel mode will be enabled.
16/68#
17
I Intel or Motorola Bus Select.
When 16/68# pin is HIGH, 16 or Intel Mode, the device will operate in the Intel
bus type of interface.
When 16/68# pin is LOW, 68 or Motorola mode, the device will operate in the
Motorola bus type of interface.
RESET
(RESET#)
45
I When 16/68# pin is HIGH for Intel bus interface, this input becomes RESET
(active high). When 16/68# pin is LOW for Motorola bus interface, this input
becomes RESET# (active low).
A 40 ns minimum active pulse on this pin will reset the internal registers and all
outputs. The UART transmitter output will be held HIGH, the receiver input will be
ignored and outputs are reset during reset period (see Table 15).
4