Ham Radio LoRa APRS using CA2RXU firmware - writing to SX127x

[arizonajon1]

Hi - I'm new to this group, I've been using Ricardo CA2RXU's firmware to develop a wide-area 4.56 kbps (BW125, SF7, CR4:6) 433 MHz LoRa APRS network here in Phoenix AZ USA. The gear is mostly LilyGO paxcounter V1.6.1 boards and qrp-labs units. It's kinda tied to the greater APRS network via aprx.

Now that I have the network running fairly well, I want to dig more into the nuts and bolts of Semtech chip configuration. Ricardo's firmware includes radiolib.

He uses calls like

radio.setBandwidth(signalBandwidth);
radio.setCodingRate(currentLoRaType->codingRate4);

which I think are to radiolib and I'm trying to figure out how those strings are parsed within radiolib.

I'm especially interested in being able to customize RegPaConf, RegPaRamp, RegLna, etc., but so far I don't see how his parameters sent to the radio via radiolib actually get parsed within radiolib and applied to the radio. As well, while I am aware of the CAD deficiencies of the SC127x family, I'd still like to tinker with CAD. The qrp-labs units use the SX126x family, which has much improved CAD. In any event, I'd like to be understand how CAD is used by his firmware; possibly, it's all invisible to him and completely managed in radiolib.

Can someone point me to the right folders and files? Say for RegPaConf? Or am I looking in the wrong place?

Cheers and 73 - Jon N7UV

[jgromes]

I don't know what the "Ricardo CA2RXU's firmware" is, so I can't confirm or deny whether it is actually using RadioLib, though it seems likely from the methods you have posted.

how those strings are parsed within radiolib.

Not sure what you mean by "string parsing" - there are no strings there, just public methods taking arguments. See this page for the API reference of SX1278, including the methods you mentioned.

Regarding changing specific registers, RadioLib does not give a (normal) user* the ability to directly edit registers, as sometimes that can lead to destructive actions. Instead, we provide a high-level API that lets you change functional parameters. For example, instead of digging inside RegPaConf, we provide a method setOutputPower that configures the registers for you so taht you reach your desired output power level (say 10 dBm) and ensures you don't end up with invalid configuration. So the real question is - what are you trying to achieve? Maybe there is a public method that does that, maybe not and it can be added.

I'd like to be understand how CAD is used by his firmware

Then that's probably a question best addressed to the other project? RadioLib supports CAD, see the examples, that's the only way I can answer that question.

* There is a way to access registers directly, in God mode. However, that is mostly intended for debugging/testing and really should not be used to workaround missing features. And of course, you might brick your module.