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wirelessinfrared

How fast (milliseconds) do IR commands typically repeat?


I am trying to mimic a remote control IR signal via serial. I am curious about IR transmission speeds. Is there a standard or typical speed?

The idea is to send a command

  loop
     {
     key up
     delay (x milliseconds)
     }

The idea is to key the command at about the same rate that the remote control would.


Solution

  • I believe the most common protocol for remote control is RC5, developped by Philips in 80s. If you have a few infra-red remote it is very likely at least one of them uses this protocol.

    RC5 modulates the signals at 36 kHz. It transmit 14bit during a 25ms timeframe. You can find more details: (including schema with the timings...)

    http://www.lennard.net.nz/electronics/rc5remote.html https://en.wikipedia.org/wiki/RC-5

    For data transmission (send and receive) there are other protocol such as IrDA. (found in PDA...).

    Trying to mimic IR signal on the serial port is fine but I think you would have more fun with a IR emitter. You should be able to build an serial port Infrared emitter.

    For exemple: http://wiki.johnroy.com/serial-ir-transmitter

    Personally I've done this with an Arduino board and a IR led.