doubt in interfacing wireless sensors
i am trying to interface wireless magnetic contact sensor , pir detector with MRF49xa tranceiver from microchip but the problem is wireless sensors are ASK modulated and MRF49xa is FSK it will be still possible for wireless sensors to transmit and receve correct data in MRF49xa ?
please can someone help me on this?
No, unfortunately I think the modulations have to match.
You'll just have to get a different module, perhaps one that can do both even. Speaking of both, if you can't pick another module or sensors, build a repeater from one modulation to the other.
indeed, that chip seems to be FSK modulation only. You need one that is "OOK" modulation.
Additionally that chip uses: "The Clock Recovery Circuit (CLKRC) is used to render
a synchronized clock source to recover the data using
an external microcontroller. The CLKRC works by
sampling the preamble on the received data. The
preamble contains a sequence of 1 and 0....". So UNLESS your sensor has the exact preamble sequence the chip recognizes...nothing comes out but jibberish. You want a much more stupid chip that just creates 1's and 0's from the amplitude level, and does no clock recovery/preamble stuff.
try this one:
http://www.onsemi.com/pub_link/Colla...NCV53480-D.PDF
you just have to adjust the capacitors on AMPOS and AMNEG pins to match your data rate.