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3-4200-D1-2.0-0403
11
STIr4200
USB/IrDA Bridge Controller
OFFICIAL
PRODUCT
DOCUMENTA TI ON
5.1.2.
FIR Transmit Frame
The FIR rate is 4 Mbps The frame organization is detailed in Figure 5.
0x55
0xAA
LSB size
MSB size
0x7E
0x7E
BOF = Beginning of frame
Header ID
Data
Data
Data
Data
Data
Data
A
CI
Address/Control/Information Fields
Special characters must be escaped
Original Data
Escaped Data
0x7D
0x7D 0x5D
0x7E
0x7D 0x5E
0x7F
0x7D 0x5F
LSB CRC
MSB CRC
FCS : 32 bit CRC-IEEE802
0x7E
EOF - End of frame
Number of following bytes
Data
0x7E
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
0x7F
PREAMBLE : These characters
cause the STIr4200S to generate the
preamble sequence used by the
receiving device for synchronization.
There must be exactly 16 characters.