example_rxtx_threaded.py does not work

[noeldum]

example_rxtx_threaded.py does not work and should probably not work.

To help us diagnose the issue I have cut down the code to a bare minimum.

This is first a simple code that works. Just to make sure my hardware and OS setup are right.

from RFM69 import Radio, FREQ_433MHZ

node_id = 2
network_id = 0

with Radio(FREQ_433MHZ, node_id, network_id, encryptionKey="TOPSECRETPASSWRD") as radio:
    while True:
        packet = radio.get_packet()
        print (packet)

This works pretty well and I do get messages transmitted here.

Now I adapted this same code to work with a single thread similar to the structure of the example

from RFM69 import Radio, FREQ_433MHZ
import threading

node_id = 2
network_id = 0

def receiveFunction(radio):
    while True:
        packet = radio.get_packet()
        print (packet)

with Radio(FREQ_433MHZ, node_id, network_id, encryptionKey="TOPSECRETPASSWRD") as radio:
    receiveThread = threading.Thread(target = receiveFunction, args=(radio,))
    receiveThread.start()

This second script does not work. When I transmit to this node the print does not output anything.
My speculation is that it should not work. The variable radio defined inside the thread has maybe escaped the with statement and it is maybe what is causing the issue.

This adapted code below does work however but has a major problem.

from RFM69 import Radio, FREQ_433MHZ
import threading

node_id = 2
network_id = 0

def receiveFunction():
    with Radio(FREQ_433MHZ, node_id, network_id, encryptionKey="TOPSECRETPASSWRD") as radio:
        while True:
            packet = radio.get_packet()
            print (packet)
receiveThread = threading.Thread(target = receiveFunction)
receiveThread.start()

The problem with this last code (although correctly receiving packets) does not allow us to use the variable radio for the tx part. Which is the whole point of the threading.

If someone has any ideas how to fix this example that would help.

[noeldum]

I left this aside for now and I am using the async/await solution which seems to work for me. Although I clearly prefer the threading way.

Does rpi-rfm69 need some lock implemented to be thread safe? I could not see any in the code.
Or do we not need any lock if using the same class instance for both rx and tx?

[noeldum]

I never manage to get the threading example working the way it is just now.

I did manage to get rx and tx working together using threading. See my version of the example below.
I hope this will help someone with that same problem.

import threading, time, signal
from RFM69 import Radio, FREQ_433MHZ       

# ----------  user config  ----------
NODE_ID      = 2          # this Raspberry Pi
NETWORK_ID   = 0
FREQ_BAND    = FREQ_433MHZ
BOARD        = dict(isHighPower=True, encryptionKey="TOPSECRETPASSWRD")

def radio_rx(radio):
    while RUN:
        pkt = radio.get_packet(timeout=1)      # non‑blocking
        if pkt:
            print(pkt)

def radio_tx(radio):
    while RUN:
        node = 1
        payload = "hello"
        ok = radio.send(node, payload, attempts=3, wait=100)
        print("tx done.")
        time.sleep(5)

def halt(*_):
    global RUN
    RUN = False

if __name__ == "__main__":
    RUN = True
    for sig in (signal.SIGINT, signal.SIGTERM):
        signal.signal(sig, halt)

    with Radio(FREQ_BAND, NODE_ID, NETWORK_ID, verbose=False, **BOARD) as radio:
        threading.Thread(target=radio_rx, args=(radio,), daemon=True).start()
        threading.Thread(target=radio_tx, args=(radio,), daemon=True).start()
        while RUN:
            time.sleep(1)

    print("Stopped cleanly.")