# If you ever want to make this code better, please do

# but for the love of God, please save this code first.

# It is written in circuitpython to prevent the need

# to compile code, and the RFM69 does not work with

# micropython.

import board

import analogio

import digitalio

from time import sleep

import math

import adafruit_rfm69

import busio

RoomNum = 10 # What room number is this in

SenderRoom = 10 # What room number reports to the receiver

RoomQuant = 12 # How many rooms are there

RecAddr = 254 # What's the address of the receiver

Radio_Freq_Mhz = 915.0 # What's the frequency of the radio

RetryAmount = 3 # How many times to retry sending the packet

min_okay = 12493 # Approx 20 deg C

max_okay = 9571 # Approx 26 deg C

led = digitalio.DigitalInOut(board.GP25) # Onboard LED

led.direction = digitalio.Direction.OUTPUT

CS = digitalio.DigitalInOut(board.GP13) # Pin 17

CS.direction = digitalio.Direction.OUTPUT

RESET = digitalio.DigitalInOut(board.GP6) # Pin 9

RESET.direction = digitalio.Direction.OUTPUT

SCK = board.GP10 # Pin 14

MOSI = board.GP11 # Pin 15

MISO = board.GP12 # Pin 16

spi = busio.SPI(SCK, MOSI, MISO)

rfm69 = adafruit_rfm69.RFM69(spi, CS, RESET, Radio_Freq_Mhz, baudrate=1000000)

#rfm69.reset()

rfm69.xmit_timeout = 10.0

#rfm69.freq_mhz = Radio_Freq_Mhz

rfm69.tx_power = 20

rfm69.node = RoomNum

rfm69.destination = RecAddr

#rfm69.encryption_key = (b'x00x00x00x00x00x00x00x00x00x00x00x00x00x00x00x00')

adcpin = board.GP26 # Pin 31

thermistor = analogio.AnalogIn(adcpin)

resend_time = 1

def ask_all(radio):

send_packet = ''

temp_list = []

room_packet = ''

for a in range(RoomQuant):

temp_list.append('')

for b in range(RoomQuant):

digitnum = str(b + 1)

if len(digitnum) == 1:

digitnum = '0' + str(b + 1)

if not int(digitnum) == RoomNum:

radio.send(bytes('query','utf-8'), destination = int(digitnum))

sleep(.5)

room_packet = radio.receive(timeout = 1.0)

if room_packet == None:

room_packet = str('0')

else:

room_packet = temp_retrieve()

temp_list[b] = digitnum+room_packet

for c in range(RoomQuant):

send_packet = send_packet + temp_list[c]

return send_packet

def temp_retrieve():

#Voltage dividor

Vin = 3.3 # Pin 35

Ro = 7500 # 10k resistor 10000 was initial setting, changed for calibration

#Steinhart constants

A = 0.00110683

B = 0.000238464

C = 0.00000006507394

# Get voltage value from ADC

adc = thermistor.value

print(adc)

Vout = (Vin/65535)*adc

# Calculate resistance

Rt = round((Vout * Ro) / (Vin - Vout),0)

# Rt = 10000 # Used for testing. Setting Rt to 10k equates approx 25C

# Steinhart - Hart equation

TempK = 1 / (A + (B * math.log(Rt)) + C * math.pow(math.log(Rt), 3))

# Convert from K to C

TempC = TempK - 273.15

TempF = (TempC * (9/5)) + 32

print(Rt, TempC, TempF)

return temp_check(Rt)

def temp_check(digis):

if digis < max_okay:

return '1'

elif digis >= max_okay and digis < min_okay:

return '2'

elif digis >= min_okay:

return '3'

temp_retrieve()

while True:

led.value = True

if SenderRoom == RoomNum:

tx_packet = ask_all(rfm69)

print(tx_packet)

for x in range(RetryAmount):

rfm69.send(bytes(tx_packet, 'utf-8'))

sleep(5)

else:

rx_packet = rfm69.receive(timeout = 10, keep_listening = False)

if not rx_packet == None:

tx_packet = temp_retrieve()

print(tx_packet)

sleep(.2)

led.value = False

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