You simply turn the IR LED ON for 13uS, then OFF for 13uS - this gives you a 38KHz carrier, it's VERY simply to do with a PIC running at 4MHz (just use NOP's for the timing), at 20MHz use a loop.raedbenz said:ok i have read about SIRC's code..
but i am asking about the hardware that will modulate the IR 38KHz beam with data?? what is the design technique?
No, what would be the point? - you're adding an extra IC for no gain.raedbenz said:
Sorry, but you're talking rubbish, we are already talking about using an IR receiver IC, which provides a logic level demodulated output. You can't just send standard serial information over an IR (or RF) serial link, there are limitations in the path that cause problems. Hence the use of Manchester coding, or similar.Sceadwian said:For receiving it's probably easier to buy an IR receiver module at the carrier frequency you're using, it's a WHOLE lot easier than trying to decode it yourself, and you can feed it directly in a PIC's UART.
Yes, you still need to code the data - you can buy radio modules with it built-in, but these are more expensive - essentially they have a PIC on-board. RF Solutions even sell pre-programmed PIC's to do it!.raedbenz said:does the RF signals work the with same concept...if i use a FSK or ASK IC??