Author Topic: Problem with RFM69 (library?) and teensy (v3.2 and 4.0)  (Read 140 times)

Uncle Buzz

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Problem with RFM69 (library?) and teensy (v3.2 and 4.0)
« on: January 09, 2020, 10:23:11 AM »
Did someone try the RFM69 radios with teensy board ?
I have a strange bug, trying teensy 3.2 and 4.0 as gateway with RFM69 library (some minor changes to adapt to board definition) and it works well for 2-5s... then all the network is downed by a "DDoS" spam from the teensy node...

If I use only moteino nodes, everything is working well, but if I use a teensy board as gateway with the same code, I can receive some messages then the RSSI which is about -29db while 2 nodes are communicating, about -90db when "silent", is saturated at -10db until I disconnect the teensy board.

It works well if I block any reply from the gateway (no ACK) but with ACK replies, firsts are ok, then the radio of the teensy enter in burst mode...

Did someone face this problem before?

Felix

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Re: Problem with RFM69 (library?) and teensy (v3.2 and 4.0)
« Reply #1 on: January 09, 2020, 01:34:25 PM »
"DDoS" spam from the teensy node" eh? That's quite a good first I heard about RFM69 ::)

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-90db while silent
That's still well above the noise floor (~ -100dB with regular lib settings).
Maybe you have some noise issues and need to isolate the RFM69 power supply from the teensy.

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then the radio of the teensy enter in burst mode
How did you determine that?

Uncle Buzz

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Re: Problem with RFM69 (library?) and teensy (v3.2 and 4.0)
« Reply #2 on: January 09, 2020, 02:15:12 PM »
a standard communication when it works is at about -29db (node near each other), but when the rf transmission is broken, other nodes see -10db at RSSI, it comes back to noise floor (I should have said below -90db since it's the threshold value to start a new transmission) when I shut down the teensy node... So the teensy's radio is sending something that "locks" the frequency with high power (I said burst mode, but maybe it means something else, "DDoS" is maybe a better image)