And to select Tuner on the amp, you use predata of 40040500. Like for TV, Stereo, VCR, Amp, etc.Īnd I found with my Technics Amp, which has a built in radio receiver, the amp functions use 32 bit predata of 40040500, but the radio receiver functions use 32 bit predata of 40040520. Then for various gizmos, a manufacturer might have different predata. And that would be separate as to predata / command. Then to make this even more fun, some manufacturers send the data Least Significant Bit first - Others LSB last. Older might have 16 bit command data, newer might have 24 or 32 bit command data. Older might have 8 bit predata, then newer models might have 16 bit predata. With the same manufacturer, they may have different bit lengths. The bits sent might be on longer than off for a 1 in some cases, or off longer than on for a 1 in other cases.Īnd there is a start bit, then predata, and then the command, and then a stop bit typically. Then as with everything else in the electronics business, NOTHING is standard! And those model numbers might be the remote control model number rather than the receiver model number! And use fast transistors to amplify the signals.įor the 38 kHz part, the following Pic PWM calculator is a BIG help.įYI - The lirc.sourceforge link above has an Onkyo folder, then different model IR specifications in that folder. Then connected the two outputs to the IR LED. What I did with the Pic was send the 38 kHz out one pin and the "bits out another pin. The following is Volume Up for an older Technics stereo. Then from that IR kit software, when receiving an IR transmission, it will look like the following on your PC serial terminal. For this you can use an IR receiver and a Parallax Propeller microcontroller along with the "IR Kit" object (software) from the Propeller object exchange. Then you will need to "see" the "bits" you are transmitting (to debug your code and find problems if it does not work). Then if you are building an IR transmitter, you need to be able to "see" that your carrier is the correct frequency. Then just about every remote code you can think of is in the LIRC database at these links. And the Sony SIRC protocol is well documented. Or the other way around, you could test an IR receiver with the *known* working Sony remote. Then if you work on making a Sony remote transmitter, you could just try Volume Up for starters, then you could point your transmitter at your TV and see if it works. For example maybe you have a Sony TV and a Sony remote for that TV. If you are wanting to make an IR transmitter and receiver, it would be a WHOLE lot easier if you have an "off the shelf" remote and receiver for the protocol you want to use. So if for example you are sending 37 kHz, that IR receiver may not receive *anything*! Yet increase the speed of your carrier a little to 37.5 kHz, then suddenly everything works! For example ONLY very close to 38 kHz for one specific IR receiver. Then they don't tell you that IR receivers will only receive a narrow range of "carrier frequency". And then there is a "combination" of signals being transmitted (38 kHz carrier + that switched on/off to send bits). The hard part is the signals are being transmitted so fast, you can't "see" what is going on. I programmed an entire Technics remote control transmitter on a Pic 16F1939 in assembly language, and I must say it was one of the most difficult things I have ever done.
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