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You have two microcontrollers, A & B, that you are attempting to have communicate via UART connection (sending serial data) using two tranceivers inplace of the wire, yes?
And both tranceivers are transmitting and receiving some type of IR signal, just not the signal you are expecting?
Have you tried the datasheet's recommendation of a 12pF cap between RX and ground?
I noticed the transmitting IR transceiver heats up after about a minute of constant transmitting
QuoteHave you tried the datasheet's recommendation of a 12pF cap between RX and ground?I now have a 10pF cap between Rx and ground . . . but looking at the datasheet, perhaps I should have tried something larger:QuoteUnder extreme EMI conditions as placing anRF-transmitter antenna on top of the transceiver, werecommend to protect all inputs by a low-pass filter,as a minimum a 12 pF capacitor, especially at theRXD port. The transceiver itself withstands EMI atGSM frequencies above 500 V/m.My wires to the transceivers from the UART are about 8 inches long.Quote9600 is approaching the upper limit of what i have got IR to work at.try the lowest baud rate you can.It claims to do from 9600 to 115kQuoteOn page 2 of the data sheet in the Pin description table =>"During transmission the RXD output is active (echo-on)."Did you consider that?Yeap, the Rxd is connected to the Rxd of my uart. Its verified with a multimeter and my digital camera.QuoteI would send a low frequency square wave into TXD. Based on the above statement one should see that square wave on the RXD pin of the transmitting device itself.It will only transmit high for no more than 50us, as the datasheet says on page 8. I verified this, and yeap, a squarewave only worked for 50us then it went low.GHF, I didn't really understand what you were trying to say. I think you are trying to say that it inverts the signal? But wouldn't it invert it back after being received by the other transceiver? I'll bring this to work on monday and look at the signals on an scope.
Under extreme EMI conditions as placing anRF-transmitter antenna on top of the transceiver, werecommend to protect all inputs by a low-pass filter,as a minimum a 12 pF capacitor, especially at theRXD port. The transceiver itself withstands EMI atGSM frequencies above 500 V/m.
9600 is approaching the upper limit of what i have got IR to work at.try the lowest baud rate you can.
On page 2 of the data sheet in the Pin description table =>"During transmission the RXD output is active (echo-on)."Did you consider that?
I would send a low frequency square wave into TXD. Based on the above statement one should see that square wave on the RXD pin of the transmitting device itself.
GHF, I didn't really understand what you were trying to say. I think you are trying to say that it inverts the signal? But wouldn't it invert it back after being received by the other transceiver? I'll bring this to work on monday and look at the signals on an scope.
So, are you at liberty to give us some more details yet? IrDA seems like a really useful project, but I never got into it because of all the high-level stuff it's buried in