Public Version
UART/IrDA/CIR Overview
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Table 19-2. UART IrDA Mode Baud Rates, Divisor Values, and Error Rates
Baud Rate
IR Mode
Encoding
Divisor
Error (%)
2400
SIR
3/16
1250
0
9600
SIR
3/16
312
0.16
19,200
SIR
3/16
156
0.16
38,400
SIR
3/16
78
0.16
57,600
SIR
3/16
52
0.16
115,200
SIR
3/16
26
0.16
576,000
MIR
1/4
2
0
1,152,000
MIR
1/4
1
0
4,000,000
FIR
4 PPM
(1)
1
0
(1)
PPM = pulse-position-modulation
NOTE:
The maximum baud rate required of the module does not depend on the change of OPP.
19.1.3 CIR Features
The CIR mode uses a variable pulse-width modulation (PWM) technique (based on multiples of a
programmable t period) to encompass the various formats of infrared encoding for remote-control
applications. The CIR logic transmits data packets based on a user-definable frame structure and packet
content.
The CIR (UART3 only) includes the following key features to provide CIR support for remote control
applications:
•
Transmit mode only (receive mode is not supported)
•
Free data format (supports any remote-control private standards)
•
Selectable bit rate
•
Configurable carrier frequency
•
1/2, 5/12, 1/3, or 1/4 carrier duty cycle
2872
UART/IrDA/CIR
SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated