xr16v2751im Exar Corporation, xr16v2751im Datasheet - Page 31

• Manufacturer Part Number: xr16v2751im
• Description: High Performance Duart With 64-byte Fifo And Powersave Feature
• Manufacturer: Exar Corporation

REV. 1.0.1
MCR[0]: DTR# Output
The DTR# pin is a modem control output. If the modem interface is not used, this output may be used as a
general purpose output.
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MCR[1]: RTS# Output
The RTS# pin is a modem control output and may be used for automatic hardware flow control by enabled by
EFR bit-6. The RTS# pin can also be used for Auto RS485 Half-Duplex direction control enabled by FCTR bit-
3. If the modem interface is not used, this output may be used as a general purpose output.
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MCR[2]: Reserved
OP1# is not available as an output pin on the V2751. But it is available for use during Internal Loopback Mode.
In the Loopback Mode, this bit is used to write the state of the modem RI# interface signal.
MCR[3]: OP2# Output / INT Output Enable
This bit enables or disables the operation of INT, interrupt output. If INT output is not used, OP2# can be used
as a general purpose output. Also, if 16/68# pin selects Motorola bus interface mode, this bit must be set to
logic 0.
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MCR[4]: Internal Loopback Enable
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MCR[5]: Xon-Any Enable
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MCR[6]: Infrared Encoder/Decoder Enable
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MCR[7]: Clock Prescaler Select
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Logic 0 = Force DTR# output HIGH (default).
Logic 1 = Force DTR# output LOW.
Logic 0 = Force RTS# HIGH (default).
Logic 1 = Force RTS# LOW.
Logic 0 = INT (A-B) outputs disabled (three state mode) and OP2# output set HIGH(default).
Logic 1 = INT (A-B) outputs enabled (active mode) and OP2# output set LOW.
Logic 0 = Disable loopback mode (default).
Logic 1 = Enable local loopback mode, see loopback section and
Logic 0 = Disable Xon-Any function (default).
Logic 1 = Enable Xon-Any function. In this mode, any RX character received will resume transmit operation.
The RX character will be loaded into the RX FIFO, unless the RX character is an Xon or Xoff character and
the V2751 is programmed to use the Xon/Xoff flow control.
Logic 0 = Enable the standard modem receive and transmit input/output interface (default).
Logic 1 = Enable infrared IrDA receive and transmit inputs/outputs. The TX/RX output/input are routed to the
infrared encoder/decoder. The data input and output levels conform to the IrDA infrared interface
requirement. While in this mode, the infrared TX output will be idling LOW.
PAGE 19.
Logic 0 = Divide by one. The input clock from the crystal or external clock is fed directly to the Programmable
Baud Rate Generator without further modification, i.e., divide by one (default).
Logic 1 = Divide by four. The prescaler divides the input clock from the crystal or external clock by four and
feeds it to the Programmable Baud Rate Generator, hence, data rates become one forth.
HIGH PERFORMANCE DUART WITH 64-BYTE FIFO AND POWERSAVE FEATURE
31
Figure
12.
SEE”INFRARED MODE” ON
XR16V2751