# Example to send a packet periodically
# Author: Jerry Needell
#
import time
import board
import busio
import digitalio
import adafruit_rfm69

# set the time interval (seconds) for sending packets
transmit_interval=10

# Define radio parameters.
RADIO_FREQ_MHZ   = 915.0  # Frequency of the radio in Mhz. Must match your
                          # module! Can be a value like 915.0, 433.0, etc.

# Define pins connected to the chip.
CS    = digitalio.DigitalInOut(board.CE1)
RESET = digitalio.DigitalInOut(board.D25)

# Initialize SPI bus.
spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)

# Initialze RFM radio
rfm69 = adafruit_rfm69.RFM69(spi, CS, RESET, RADIO_FREQ_MHZ)

# Optionally set an encryption key (16 byte AES key). MUST match both
# on the transmitter and receiver (or be set to None to disable/the default).
rfm69.encryption_key = b'\x01\x02\x03\x04\x05\x06\x07\x08\x01\x02\x03\x04\x05\x06\x07\x08'

# initialize counter
counter = 0
#send a broadcast mesage
rfm69.send(bytes("message number {}".format(counter),"UTF-8"))

# Wait to receive packets.
print('Waiting for packets...')
#initialize flag and timer
send_reading=False
time_now=time.monotonic()
while True:
    # Look for a new packet - wait up to 5 seconds:
    packet = rfm69.receive(timeout=5.0)
    # If no packet was received during the timeout then None is returned.
    if packet is not None:
        # Received a packet!
        # Print out the raw bytes of the packet:
        print('Received (raw bytes): {0}'.format(packet))
        # send reading after any packet received
    if time.monotonic()-time_now>transmit_interval:
        #reset timeer
        time_now=time.monotonic()
        #clear flag to send data
        send_reading=False
        counter = counter + 1
        rfm69.send(bytes("message number {}".format(counter),"UTF-8"))
