at91sam9263 ATMEL Corporation, at91sam9263 Datasheet - Page 530

• Manufacturer Part Number: at91sam9263
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

33.6.5.1
Figure 33-24. IrDA Modulation
33.6.5.2
6249D–ATARM–20-Dec-07
IrDA Modulation
IrDA Baud Rate
For baud rates up to and including 115.2 Kbits/sec, the RZI modulation scheme is used. “0” is
represented by a light pulse of 3/16th of a bit time. Some examples of signal pulse duration are
shown in
Table 33-9.
Figure 33-24
Table 33-10
the requirement on the maximum acceptable error of ±1.87% must be met.
Table 33-10. IrDA Baud Rate Error
Transmitter
Baud Rate
2.4 Kb/s
9.6 Kb/s
19.2 Kb/s
38.4 Kb/s
57.6 Kb/s
115.2 Kb/s
Peripheral Clock
3 686 400
20 000 000
32 768 000
40 000 000
3 686 400
20 000 000
32 768 000
40 000 000
3 686 400
20 000 000
Output
TXD
Table
gives some examples of CD values, baud rate error and pulse duration. Note that
shows an example of character transmission.
Bit Period
IrDA Pulse Duration
Start
33-9.
Bit
0
1
Baud Rate
115 200
115 200
115 200
115 200
57 600
57 600
57 600
57 600
38 400
38 400
0
1
Data Bits
0
0
AT91SAM9263 Preliminary
Pulse Duration (3/16)
78.13 µs
19.53 µs
9.77 µs
4.88 µs
3.26 µs
1.63 µs
CD
11
18
22
22
36
43
33
2
4
6
1
1
16
3
Baud Rate Error
0
Bit Period
Stop
0.00%
1.38%
1.25%
1.38%
0.00%
1.38%
1.25%
0.93%
0.00%
1.38%
Bit
1
Pulse Time
1.63
1.63
1.63
1.63
3.26
3.26
3.26
3.26
4.88
4.88
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