Hello everyone, I am currently building a weather station with an arduino uno as a microcontroller. I created an online databank to store the collected weather data, but now i need a way to communicate with the internet. I thought about lorawan, to connect to a nearby ttn gateway, but I have some problems. The Arduino Uno uses 5V SPI logic, but I only seem to find good lora modules and tutorials using 3.3V SPI logic. Is there a way to still use such modules, or are there some good modules that use the 5V logic? And how do I after connecting the module communicate with the Gateway?
All LoRa modules use a Semtech LoRa device, which is 3.3V logic.
Using 3.3V logic Arduinos is by far the easiest way to use LoRa modules and there ought to be heaps of tutorials out there for connecting to LoRaWAN.
Some companies make LoRa Shields for 5V logic Arduinos or modules that include the logic conversion stuff, eg;
Buy the right frequency band for LoRaWAN in your part of the World.
I use AI thinker RA01h 3.3V lora module.
Power you need to solve your case: use 5V input and a step down DCDC converter: 5->3.3V , use common ground. google gave me this: Amazon.com : 5V to 3.3V
you could save yourself trouble by moving to a board which incorporates a microcontroller and a LoRa module, e.g. ttgo-lora32, Adafruit Feather 32u4 LoRa, TTGO-Beam, Hiltec LoRa 32, The Things UNO, etc
this saves the problems of level shifters, jumper wires which give poor connections and intermittent faults, etc, e.g. see river level monitoring
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if you still wish to use the UNO have a look at the Grove_LoRa_E5
I have used it for LoRa point-to-point and LoRaWAN to the Things V3 server
it uses serial communications so simpler to interface than SPI
on a UNO use AltSoftSerial (Can simultaneously transmit and receive.) Tx pin 9 Rx pin 8
use a potential divider on the UNO Tx (5V logic) to E5 Rx (3.3V logic)
EDIT: be careful some LoRa modules only implement the LoRa radio - OK for LoRa P2P
in such a case the LoRaWAN stack runs on a host microcontroller - I doubt the UNO would support such complex software
Ok thank you! Yes i noticed that some only are able to do P2P communication, which made it hard to find something fitting. The divider is no problem for me, its only important that i can connect to a gateway.
It has amazed me what the Uno is capable of doing. Paired with a Dragino LoRa Transceiver, I have been able to send static images via LoRa P2P. Unfortunately, Dragino no longer manufactures that transceiver. Am unable to get their replacement to carry out a simple AT query and deliver the complete return message. The existing project's software and documentation can be found at GitHub - SoothingMist/Scalable-Point-to-Point-LoRa-Sensor-Network: Builds a peer-to-peer network of LoRa transceivers for remote sensing. Uses flood-messaging to eliminate need for LoRaWAN and third-party services..