I'm trying to transmit OOK using the JeeNode, and it's not going too well.
Basically OOK is just a matter of turning the transmitter on and off at the right intervals - easy!
So I took the original transmitter, pressed the button I want the JeeNode to emulate, and noted the on/off waveform on my scope - it can't see the 433MHz RF, but it can see the digital signal where it enters the RF circuit.
Then I wrote some software to set up the RFM12 registers so it will operate at 433.92MHz:
Frequency Setting command, 0xA620
and created a function to turn the transmitter on and off at the correct intervals to reproduce the OOK code:
0x8209 = off 0x8238 = on
So far so good.
But it doesn't work. As I can't detect the presence of 433MHz RF, I modified my on/off function to get it to turn the RF12 external oscillator output on and off with the transmitter. So now when I put my scope on the ext_osc pin, I can see that the OOK code is being received by the RF12, and I can verify (and fine-tune) the OOK timing to avoid the SPI bus introducing inaccuracies. My code doesn't need anything like as much tweaking as the standard JeeNode software BTW, which is a bit interesting.
But it still doesn't work. Now I find myself wondering if this is related to the TX Configuration Control command (0x98) which allows me to adjust the Frequency Deviation. I have no idea what this is, and would be tempted to select zero, but there is no option for this.
So to cut a long story short, does anyone know what I should be doing with the Frequency Deviation register, or have any other constructive advice ?