Binary data transmission

End Devices (Nodes)
1

I am trying to send data over LoRa every ten minutes from my end node device.

Here is dummy data:

char tx_buffer;
tx_buffer = 0x42;

While sending this command over LoRa, I see two options

char buffer[100];

Option1:
sprintf(buffer, "AT+SEND=PortNumber:%c", tx_buffer);

This when printed out is
AT+SEND=PortNumber:B

and B is sent out over LoRa and seen on Things Network as 0x42

Option2:
sprintf(buffer, "AT+SENDB=PortNumber:%u", tx_buffer);

This when printed out is
AT+SEND=PortNumber:66

and 66 is sent out over LoRa and seen on Things Network as 0x66

I wanted to understand if there was any merit in sending data here as text versus as binary. I see the same number of bytes on binary.

Maybe I am not thinking along right lines here. Any help would be much appreciated

2

The most compact format, which is better for your battery and the RF bandwidth shared by the community, is binary - once you start using text, it’s a slippery slope.

However it very much depends on which module you are using.

As an example, the RAK module uses at+send=lora:<port>:<data> The spec says they’d like it as a Hex string which they translate in to a binary format before sending. It’s done this way to facilitate transmission over a serial port.

So the key question here is, which module are you using?

3

I am working with STM32 Lora discovery kit which has a murata module. Also, I use I-Cube-LRWAN package