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IR with learning device??? — Parallax Forums

IR with learning device???

killervettekillervette Posts: 16
edited 2006-09-01 00:50 in BASIC Stamp
I looked at the IR buddy pair but i am not sure that will work.· I have a mini blind tilt control that uses a IR remote.· I want to emulate the remote with a stamp board.· First off, is this possible...second what IR component can i add to make it work?

Comments

  • allanlane5allanlane5 Posts: 3,815
    edited 2006-08-31 23:55
    The IR-Buddy has a small co-processor that decodes the "Phillips RC-5" protocol -- and ONLY the Phillips RC-5 protocol. If, magically, your mini-blind tilt control happens to USE the Phillips RC-5 protocol, you're golden. It's very unlikely.

    So, your first goal, is to find out what protocol your mini-blind tilt control does use. The easiest way to do that is with an IR-Decoder (a small, 3-pin device, which decodes a 48 KHz blinking IR LED signal). Now, every IR remote uses a different 'protocol'. The way they build this protocol is out of 1's and 0's. A '1' typically is some duration of the 48 Khz blinking light. For example, if you blink the LED for a period of 600 uSec, then leave it off for 600 uSec, that's a zero. If you blink it for 1200 uSec, then leave it off for 600 uSec, that's a one.

    Now, a protocol is built out of a series of these 1's and 0's -- typically a 'sync' pulse, then some data pulses. Search on the Phillips RC-5 and the Sony protocols to get more information.

    Now, what you want to do is, aim your mini-blind remote at the IR-decoder, and press buttons. You'll need to have written a small BS2 program to read the decoder, and tell you how long the pulses are. From that, you'll have to 'reverse engineer' what the protocol is your blinds are using.

    Then, you use an IR-LED and the 'FREQOUT' command to send your OWN series of 48 Khz pulses, properly timed.
  • killervettekillervette Posts: 16
    edited 2006-09-01 00:03
    cool..ok. i also may want to use this for microsofts media center remote which uses the phillips protocol, but i remember reading rc6?
  • killervettekillervette Posts: 16
    edited 2006-09-01 00:06
    ps. can you point me in the right direction as to where to buy a ir decoder.
  • allanlane5allanlane5 Posts: 3,815
    edited 2006-09-01 00:50
    One of these:

    http://www.radioshack.com/product/index.jsp?productId=2049727&cp=2032058.2032230.2032279&parentPage=family

    Yes, this one says 38 Khz, but that should work fine. In fact, if you have a BOE-BOT, the 'IR-Whiskers' are built using these parts.

    And one of these: http://www.radioshack.com/product/index.jsp?productId=2062565&cp=&pg=2&origkw=LED&kw=led&parentPage=search

    with a 470 ohm current limiting resistor.
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