xr16m698 Exar Corporation, xr16m698 Datasheet - Page 39

• Manufacturer Part Number: xr16m698
• Description: 1.62v To 3.63v High Performance Octal Uart With 32-byte Fifo
• Manufacturer: Exar Corporation

REV. 1.0.0
LCR[2]: TX and RX Stop-bit Length Select
The length of stop bit is specified by this bit in conjunction with the programmed word length.
LCR[1:0]: TX and RX Word Length Select
These two bits specify the word length to be transmitted or received.
The MCR register is used for controlling the modem interface signals or general purpose inputs/outputs.
MCR[7]: Clock Prescaler Select
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•
MCR[6]: Infrared Encoder/Decoder Enable
The state of this bit depends on the sampled logic level of pin ENIR during power up, following a hardware
reset (rising edge of RST# input). Afterward user can override this bit for desired operation.
•
•
MCR[5]: Xon-Any Enable
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•
MCR[4]: Internal Loopback Enable
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•
4.7
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.
Logic 0 = Enable the standard modem receive and transmit character interface.
Logic 1 = Enable infrared IrDA receive and transmit inputs/outputs. While in this mode, the TX/RX output/
input are routed to the infrared encoder/decoder. The data input and output levels will conform to the IrDA
infrared interface requirement. As such, while in this mode the infrared TX output will be a logic 0 during idle
data conditions. FCTR bit-4 may be selected to invert the RX input signal level going to the decoder for
infrared modules that provide rather an inverted output.
Logic 0 = Disable Xon-Any function (default).
Logic 1 = Enable Xon-Any function. In this mode any RX character received will enable Xon, resume data
transmission.
Logic 0 = Disable loopback mode (default).
Logic 1 = Enable local loopback mode, see loopback section and
Modem Control Register (MCR) - Read/Write
1.62V TO 3.63V HIGH PERFORMANCE OCTAL UART WITH 32-BYTE FIFO
BIT-1
BIT-2
0
0
1
1
0
1
1
LENGTH
BIT-0
5,6,7,8
W
6,7,8
0
1
0
1
ORD
5
39
S
W
TOP BIT LENGTH
(B
ORD LENGTH
5 (default)
1 (default)
IT TIME
1-1/2
6
7
8
Figure 11
2
(
S
))
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XR16M698