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RFM69CW@868 MHz version for AVRs

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ZeroGee:
Very nice! I'm in the process of porting the library to avr-gcc and asf for use on an xmega192a3u, and I'm wondering what you actually used for the frequency deviation + bitrate + channel filter bandwidth control.

Currently I've been able to send and recieve one packet, but the ACK has failed to either send or be recieved by the sending module. :\ That and I have to wait significant times between sending packets. I'm still working the bugs out...

RafPe:
Hey ,

Great to hear you also got working. I have not tested ACK response system yet. Can you share your init function ?

For my calculations I have used following info :

BR = 32 000 000 / (REG_BITRATE) = 32 000 000 / 0x0D05 = 32 000 000 / 33333 = 9600 b/s
W REG_FDEV :
FDEV = 32 000 000 / 2^19 * REG_FDEV = 32 000 000 / 2^19 * 0x0241 = 35 kHz

REG_RXBW accordingly to table in DS : REG_RXBW -> RxBw = 83 kHz and fc = 4% z RxBw

The following needs to applied
0,5 <= 2 * FDEV / BR <= 10
BR < 2 * RxBw
RxBw > 2 * FDEV
FDEV + BR / 2 < 500 kHz

Hope it helps

Rafal

RafPe:
To just show you it works really well and extremely fast small screenshot

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