Motorola MPC823e Reference Manual page 743

16.9.20.2 MIDDLE-SPEED IRDA PROTOCOL. The middle-speed IrDA protocol consists
of a data link layer and a physical layer.
• The data link layer is derived from the preexisting synchronous HDLC protocol
standard. The frame format follows the standard HDLC format except that it requires
two start flags. The frame consists of two start flags, an address field, a control field, an
information field, a frame check sequence field and minimum of one ending flag. 0x7E
is used for the start flag as well for the end flag.
START FLAG START FLAG
1 BYTE
• The physical layer defines the electrical parameters of the signals between the
encoder/decoder module and the infrared transducer module. The signal waveform is
shown in Figure 16-96. For 0.576 and 1.152Mb/s, the minimum and maximum pulse
duration are the nominal
tolerance).
(A)
(B)
Figure 16-96. Middle-Speed IrDA Data Format
MOTOROLA
ADDRESS CONTROL
1 BYTE 1 BYTE 1 BYTE
Figure 16-95. Middle Speed Packet Format
1
/ of the bit duration (plus or minus the protocol-defined
4
1 0 1
MPC823e REFERENCE MANUAL
Communication Processor Module
INFORMATION CRC
N BYTES 2 BYTES
DATA BITS
0 0 1 1
1/4 BIT TIME
END FLAG
1 BYTE
0
16-289