xr16l2550im Exar Corporation, xr16l2550im Datasheet - Page 27

• Manufacturer Part Number: xr16l2550im
• Description: Industry Smallest Package Uart With 2.25v To 5.5v Operation
• Manufacturer: Exar Corporation

REV. 1.1.2
LCR[4]: TX and RX Parity Select
If the parity bit is enabled with LCR bit-3 set to a logic 1, LCR BIT-4 selects the even or odd parity format.
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LCR[5]: TX and RX Parity Select
If the parity bit is enabled, LCR BIT-5 selects the forced parity format.
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LCR[6]: Transmit Break Enable
When enabled, the Break control bit causes a break condition to be transmitted (the TX output is forced to a
“space’, logic 0, state). This condition remains, until disabled by setting LCR bit-6 to a logic 0.
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LCR[7]: Baud Rate Divisors (DLL/DLM) Enable
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The MCR register is used for controlling the serial/modem interface signals or general purpose inputs/outputs.
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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4.7
Logic 0 = ODD Parity is generated by forcing an odd number of logic 1’s in the transmitted character. The
receiver must be programmed to check the same format (default).
Logic 1 = EVEN Parity is generated by forcing an even number of logic 1’s in the transmitted character. The
receiver must be programmed to check the same format.
LCR[5] = logic 0, parity is not forced (default).
LCR[5] = logic 1 and LCR[4] = logic 0, parity bit is forced to a logical 1 for the transmit and receive data.
LCR[5] = logic 1 and LCR[4] = logic 1, parity bit is forced to a logical 0 for the transmit and receive data.
Logic 0 = No TX break condition (default).
Logic 1 = Forces the transmitter output (TX) to a “space”, logic 0, for alerting the remote receiver of a line
break condition.
Logic 0 = Data registers are selected (default).
Logic 1 = Divisor latch registers are selected.
Logic 0 = Force DTR# output to a logic 1 (default).
Logic 1 = Force DTR# output to a logic 0.
Modem Control Register (MCR) or General Purpose Outputs Control - Read/Write
LCR B
X
0
0
1
1
IT
-5 LCR B
X
0
1
0
1
IT
T
-4 LCR B
ABLE
11: P
0
1
1
1
1
IT
-3
ARITY SELECTION
27
Forced parity to space, “0”
Force parity to mark, “1”
LOW VOLTAGE DUART WITH 16-BYTE FIFO
P
ARITY SELECTION
Even parity
Odd parity
No parity
XR16L2550