9 Remote control protocols
STFPC311
9.2 SPI interface IR data transmission
The IR data is sent on the DOUT pin of the SPI interface when the micro controller issues a IR
data read command. The data is sent in 3 bytes with LSB transmitted first as shown in the
Figure below:
The RC data consists of RC address, start bit, toggle bit and the RC command received. The
extra bits are stuffed with 1’s to make it a 3-byte packet. These extra bits at the end of the
packet should be ignored.
Figure 24. RC-6 protocol frame
The RC data consists of RC address, start bit, toggle bit and the RC command received. The
extra bits are stuffed with 1’s to make it a 3-byte packet. These extra bits at the end of the
packet should be ignored.
9.3 NEC remote control
This remote control protocol uses pulse distance modulation. Each bit consists of a high level of
fixed time "t", followed by a low level that varies in width. A space that is "t" represents a logic '0'
and a space that is "3t" represents a logic '1'. t = 0.56ms.
The LSB is transmitted first as shown in Figure 25
Figure 25. Pulse distance modulation.
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