QUERY · ISSUE

On Raspberry Pi Pico W, socket `accept` hangs when started in a thread

openby ggardetopened 2023-11-28updated 2024-12-17

bug

On Raspberry Pi Pico W, sockets are broken when started in a thread.
Here is a minimal broken code, hanging on socket accept (at best 1st call works):

from machine import I2C, Pin
import network, time
import _thread
try:
  import usocket as socket
except:
  import socket

#WiFi
ssid = "MySSID"
wifikey = "MyKey"

door_state = "unknown"

def web_page():
    html = """<html><head> <title>My minimal TEST</title></head><body> <h1>My minimal TEST</h1>
<p>Door state: <strong>""" + door_state + """</strong></p></body></html>"""
    return html

mywifi = network.WLAN(network.STA_IF)
try:
    mywifi.active(True)
    mywifi.connect(ssid, wifikey)
except:
    print('network config FAILED!')

for i in range(60):
    if mywifi.isconnected():
        print('network config:', mywifi.ifconfig())
        break
    else:
        time.sleep(1) # Sleep for 1 second

def DummyLoop():
    while True:
        time.sleep(10)

def WebServer():
    print("Starting webserver...")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    s.bind(('', 80))
    s.listen(5)

    while True:
        print('Webserver: Waiting on s.accept')
        conn, addr = s.accept() # Blocked here forever...
        print('Webserver: Got a connection from %s' % str(addr))
        request = conn.recv(1024)
        request = str(request)
        print('Webserver: Content = %s' % request)
        response = web_page()
        conn.send('HTTP/1.1 200 OK\n')
        conn.send('Content-Type: text/html\n')
        conn.send('Connection: close\n\n')
        conn.sendall(response)
        conn.close()
        print('Webserver: Conn.close')
        
_thread.start_new_thread(WebServer, ())
DummyLoop()

If I replace the last 2 lines with:

_thread.start_new_thread(DummyLoop, ())
WebServer()

to not start WebServer in a separate thread (Basically invert DummyLoop and WebServer), then, it just works.

MicroPython v1.21.0 on 2023-10-06; Raspberry Pi Pico W with RP2040

CANDIDATE · ISSUE

rp2: Accept not responding on Pico W after 5 mins

openby countrypaulopened 2024-09-11updated 2024-09-22

bugport-rp2

Port, board and/or hardware

Raspberry Pi Pico W

MicroPython version

MicroPython v1.23.0 on 2024-06-02; Raspberry Pi Pico W with RP2040

Reproduction

import network
import socket
import time

ssid = 'SSID'
password = 'PASSWORD'

wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(ssid, password)
while not wlan.isconnected():
    time.sleep(1)
print("Connected", wlan.ifconfig()[0])

addr = socket.getaddrinfo('0.0.0.0', 80)[0][-1]
s = socket.socket()
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(addr)
s.listen(1)

while True:
   cl, addr = s.accept()
   request = cl.recv(1024)
   cl.send("HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n")
   cl.send("<html><body>{}</body></html>".format(time.time()))
   cl.close()

Expected behaviour

I expected the Pico W to accept requests and respond with the time (single integer) indefinitely.

Observed behaviour

Running the example code (which is a simplified version of the webserver example on the RPI site) I can send requests from FIrefox to thePico W ip address and get an imediate response. If the Pico W is left about 5 minutes or more with receiving a request then it no longer appears to accept on he socket.

Additional Information

If I put a timeout on the socket of 30 seconds the Pico W works for longer than 5 minutes but does eventually stop responding.
Putting a line into the html so that it refeshes every minute will keep the Pico responding for hours.

Code of Conduct

Yes, I agree