Hello, I do not know C++ so I'm currently investigating writing a port for this in Golang over here. This is the first time I've experimented with the Dragino LoRa GPS HAT, and the first time doing something like this so I'm a little unsure of what to do since there's no documentation.

Thanks.

the transmission is working perfectly
but i'm having issues on receiving packets i'm sending123456
either i receive them corrupted or i receive them scrambled like 142356
but sometimes and rarely i receive them correctly

I have been trying to get the CRC check working properly, and found two issues. The first one is already addressed here in the pull request #2 .

The other one that prevents the code from detecting the CRC check failures is that any writing operation to the REG_IRQ_FLAGS register (even writing 0x00) causes all the IRQ flags to be reset, not just the intended ones. In the example receive function, there is this line that is supposed to clean only the RxDone flag:

writeReg(REG_IRQ_FLAGS, 0x40);

but actually it cleans all the flags, so you never detect the CRC error. A quick fix is to read the flags before doing any writing to that register. But what seems to me to be a greater problem is the fact that the datasheet says "Writing 1 resets a flag", and in reality, all flags are reset. Even the example code follows the datasheet. I have two RPI Lora Hat boards, and they both behave this way.

I just received the rpi lora/gps hat and connected it to my Raspberry Pi 3B+, on running the dragino_lora_app code, and get the following error

$ ./dragino_lora_app sender hello
Unrecognized transceiver.

System Info

Model: Raspberry Pi 3B+

No LSB modules are available.
Distributor ID:	Raspbian
Description:	Raspbian GNU/Linux 9.11 (stretch)
Release:	9.11
Codename:	stretch

Linux rpi3 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l GNU/Linux

Could you, please, add a license file so that it becomes clear how this code may be used. GPL would be fine.

Best regards

Heinrich

Hello,

I changed the spreading factor in dragino_lora_app to 10:

// Set spreading factor (SF7 - SF12)
sf_t sf = SF10;

and run "make" (of course).

But this has no effect. The server still receives SF7-messages, but not SF10-messages.

Dear bone daddy, I have the same problem with a raspberry pi 3b+ paired with the Dragino LoRa GPS hat v1.4. When the program is launched a packet is transmitted through LoRa, but after this first communication is no longer possible to send data and I have to shutdown and remove the power to the pi. The Lora-Rx blue LED stays on with a steady light after the first run, do you think this could be the issue?

$ ./dragino_lora_app sender HI
SX1276 detected, starting.
Send packets at SF7 on 868.100000 Mhz.
------------------
send: HI

$ ./dragino_lora_app sender HI
Unrecognized transceiver.

How do you solve your problem!? Thank you!
Fede

Originally posted by @theRosyProject in #5 (comment)