Node to Node Communication with a variable Spreadingfactor on AB01

#1

I read https://heltec-automation-docs.readthedocs.io/en/latest/esp32/frequently_asked_questions.html#node-to-node-communication this and i was wondering, if it possible to establish Node to Node Communication with the AB01 Board.

With the software from Github for AB01, i can only achieve Node to Node communication, when the spreading factor is also the same. I would be nice if i could archive Node to Node communication with the parameters from the link above.

I would be greatful for any feedback :slight_smile:

#2

Hi,

The answer is Yes.

#3

sorry, I can’t your meaning well. Could you explain it more?

#4

Of course!

So I am right, when those key parameters must match on both devices, when directly communicant with each other:

  1. The same sending and listening frequency: LoRa.setFrequency(frequency);
  2. The same bandwidth: LoRa.setSignalBandwidth(signalBandwidth);
  3. The same coding rate: LoRa.setCodingRate4(codingRateDenominator);
  4. The same preamble length: LoRa.setPreambleLength(preambleLength);
  5. The same sync word: LoRa.setSyncWord(syncWord);

But when I am trying to send a packet from one device to another, I notice that the spreadingfactor must also match. But i could use different codingrates.

I know the key parameters above are from the documentation of WiFi LoRa 32 and not the AB01, so are they the same?

#5

the answer is also YES.

#6

But why then must I set the Spreadingfactor as an RX Option in the Example Script?

#7

So can you show me an example code, where i dont have to set the spreadingfactor as RX Option?

#8

Still no answer? It should be possible, but i cant find any code that is able to do it on Cubecell AB01.

#9

Can you please look into the problem?

#10

hi,

your ESP32 can use this lib:

you can refer this code with your ESP32:

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#11

I am not using the ESP32 i am using the Cubecell AB-01 and i tried the pingpong code from: https://github.com/HelTecAutomation/ASR650x-Arduino/tree/8574d3df7abb322be8920831630c69f92d63f56e/libraries/LoRa/examples/LoRaBasic

But i cant use different spreadingfactors on two devices. As you pointed out in a previous message.
Also if the spreadingfactor can be different on RX/TX why is it an option in the RX settings?

#12

This code uses the lora function implemented by lorawan’s library function.

You can try to make the source code communicate.

just do it.

#13

I tried to use the libarys from Cubecell AB-01 but every time, the spreadingfactor on two devices is different, they wont recieve a packet from each other.

#14

hi,

I have tested it. it works fine:

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please confirm these information:

ESP32 device use this code:

Cubecell use this code:

#15

I can confirm this, when i am using the Cubecell code on both ASR6501 chips, they can ping each other, like you showed in your screenshot.

But the issue is, when setting the spreadingfactor on device to 8 (so changing in the code: LORA_SPREADING_FACTOR 7 to LORA_SPREADING_FACTOR 8) and leaving the spreadingfactor on the other device to the default value 7, they cant ping each other again.

Strangely enough if i change only the coding rate (LORA_CODINGRATE) to a different value, they can communicate. But didnt you say, the codingrate must be the same and the spreadingfactor can be different?

#16

hi,

sorry, this is our fault. we have updated the docs:

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