# Echo any messages received (using custom LoRa parameters).
#
# The pin configuration used here is for the first LoRa module of these boards:
# https://makerfabs.com/esp32-lora-gateway.html

from lora import LoRa
from machine import Pin, SPI
from time import sleep

# SPI pins
SCK  = 2
MOSI = 3
MISO = 4
CS   = 5
RX   = 6

# Initialize SPI
spi = SPI(0,
            baudrate=1000000,
            polarity=1,
            phase=1,
            bits=8,
            firstbit=machine.SPI.MSB,
            sck=machine.Pin(SCK),
            mosi=machine.Pin(MOSI),
            miso=machine.Pin(MISO))


spi.init()

# Setup LoRa
lora = LoRa(
    spi,
    cs=Pin(CS, Pin.OUT),
    rx=Pin(RX, Pin.IN),
    frequency=915.0,
    bandwidth=250000,
    spreading_factor=10,
    coding_rate=5,
)

# Receive handler
def handler(x):
    # Echo message
    lora.send(x)
    # Put module back in recv mode
    lora.recv()

# Set handler
lora.on_recv(handler)
# Put module in recv mode
lora.recv()

# No need for main loop, code is asynchronous