LoRa-Workshop/README.md

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# imaginaerraum LoRa Workshop
This workshop assumes you are familiar with the basics of MicroPython (see [apos's MicroPython Workshop][micropython-workshop] for an introduction).
[micropython-workshop]: https://imaginaerraum.de/git/apo/micropython-workshop
## Hardware
We use the [Wemos® TTGO LORA32 868/915Mhz board][wemos].
[wemos]: https://www.banggood.com/2Pcs-LILYGO-TTGO-LORA32-915Mhz-ESP32-LoRa-OLED-0_96-Inch-Blue-Display-p-1239769.html
## Software
We make use of the two MicroPython libraries [uPyLora by lemariva][lemariva] and [uLoRaWAN by mallagant][mallagant]. uPyLora is a driver for the SX1276 LoRa module which is connected to the ESP32.
uLoRaWAN is a library which creates LoRaWAN packages, which you can then transfer via LoRa to send data to [TheThingsNetwork][ttn].
I added a wrapper class [LoRaTransceiver](micropython/lora_transceiver.py) which makes them a bit easier to use.
[lemariva]: https://github.com/lemariva/uPyLora
[mallagant]: https://github.com/mallagant/uLoRaWAN
[ttn]: https://www.thethingsnetwork.org/
## Setup
The files you will need are all located in the `micropython/` subfolder. To get started, you can either upload the file
* `lora_transceiver.py`
and the folders
* `uPyLora/`
* `uLoRaWAN/`
* `uPySensors/`
to the ESP, or just flash [this image](micropython/esp32-image/image.bin).
Here are some examples how to use the LoRa module:
__1. LoRa sending:__
```
from lora_transceiver import LoRaTransceiver
from uPySensors.ssd1306_i2c import Display
d = Display()
# create transceiver
lora = LoRaTransceiver(display=d)
# send data
lora.send_string('imaginaerraum')
```
__2. LoRa receiving:__
```
from lora_transceiver import LoRaTransceiver
from uPySensors.ssd1306_i2c import Display
d = Display()
# create transceiver
lora = LoRaTransceiver(display=d)
# start receiving data
#lora.recv()
```
__3. LoRaWAN sending:__
```
from lora_transceiver import LoRaTransceiver
from uPySensors.ssd1306_i2c import Display
import uLoRaWAN
from uLoRaWAN.MHDR import MHDR
d = Display()
# create transceiver for LoRaWAN frequency (channel 0 = 868.1 Mhz)
lora = LoRaTransceiver(frequency=868.1E6, syncword=0x34, display=d)
# change the spreading factor
lora.setSpreadingFactor(9)
# TODO: set address and keys for LoRaWAN
devAddr = [0x00, 0x00, 0x00, 0x00]
nwkSKey = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]
appSKey = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]
devAddr_hex = " ".join(["%02X" % (x,) for x in devAddr])
nwkSKey_hex = " ".join(["%02X" % (x,) for x in nwkSKey])
appSKey_hex = " ".join(["%02X" % (x,) for x in appSKey])
print("devAddr: ", devAddr_hex)
print("nwkSKey: ", nwkSKey_hex)
print("appSKey: ", appSKey_hex)
# lorawan object for conversion of data in LoRaWAN message format
lorawan = uLoRaWAN.new(nwkSKey, appSKey)
def send_lorawan(message, frame_cnt=0):
lorawan.create(MHDR.UNCONF_DATA_UP, {'devaddr': devAddr, 'fcnt': frame_cnt, 'data': list(map(ord, message)) })
payload = lorawan.to_raw()
lora.send(payload)
print("lorawan message sent")
send_lorawan("Hello world!")
```
(you can also find these in the `examples/` subdirectory)
For more information, have a look at the documentation of the [LoRaTransceiver](micropython/lora_transceiver.py) class.