SAM7L128 Atmel Corporation, SAM7L128 Datasheet - Page 391

• Manufacturer Part Number: SAM7L128
• Manufacturer: Atmel Corporation

Specifications of SAM7L128

• Flash (kbytes): 128 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 36 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 80
• Ext Interrupts: 80
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Segment Lcd: 40
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 460
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 6
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.8 to 3.6
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

30.6.5.1
30.6.5.2
6257A–ATARM–20-Feb-08
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 30-9.
Figure 30-34
Figure 30-34. IrDA Modulation
Table 30-10
the requirement on the maximum acceptable error of ±1.87% must be met.
Table 30-10. IrDA Baud Rate Error
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
• Configure the TXD pin as PIO and set it as an output at 0 (to avoid LED emission). Disable
• Receive data
the internal pull-up (better for power consumption).
Table
gives some examples of CD values, baud rate error and pulse duration. Note that
shows an example of character transmission.
Transmitter
IrDA Pulse Duration
30-9.
Output
TXD
Baud Rate
115 200
115 200
115 200
115 200
57 600
57 600
57 600
Bit Period
Start
Bit
0
1
AT91SAM7L128/64 Preliminary
0
1
CD
11
18
22
22
36
2
4
Pulse Duration (3/16)
78.13 µs
19.53 µs
9.77 µs
4.88 µs
3.26 µs
1.63 µs
Data Bits
0
0
Baud Rate Error
1
0.00%
1.38%
1.25%
1.38%
0.00%
1.38%
1.25%
1
16
3
0
Bit Period
Stop
Bit
1
Pulse Time
1.63
1.63
1.63
1.63
3.26
3.26
3.26
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