Following success with my latest project.
Main aim being to develop a simple way of getting two Pico W’s to communicate, thought I would share the Python code I developed.
One Pico W sets itself up as a WiFi Access Point and listens for a connection from the other Pico W.
The other Pico W connects to the Access Point, collects data and sends it.
The Access Point responds with ‘success’ if data is received ok.
The code here is the basic for the communications, whatever is done with the data or how it is collected is not shown. Don’t expect the files below to run properly as they are; they need additional code to read a sensor or something and to process the received sensor data. My project used a temperature sensor and a LCD display to show the data.
Cheers
Jim
Client File
############################################################################
# Pi Pico W Client
#
# Connects to Access Point to send data
############################################################################
import os
import network
import socket
import time
import urequests
from SSID_AP import SSID_AP
############################################################################
'''
SSID_AP.py is a files in the same folder as the running program
It contains SSID and Password information
SSID_AP File: SSID_AP.py
SSID_AP = {
'ssid': 'any name you want to call the access point',
'pw': 'whatever password you decide to use'
}
'''
############################################################################
host = '192.168.10.2'
server = '192.168.10.1'
gateway = '192.168.10.1'
port = 5263
ssid = SSID_AP['ssid']
pw = SSID_AP['pw']
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
Onboard_LED = Pin("LED", Pin.OUT, value=0)
############################################################################
# Check for Server active
############################################################################
def check_SSID():
print('Checking for Network ...',ssid)
networks = wlan.scan()
found = False
for w in networks:
if w[0].decode() == ssid:
found = True
return found
############################################################################
# Display Connect Error
############################################################################
def connect_Fail(s):
Error = 'Connect Fail: '
if s == 0:
Error += 'Link Down'
elif s == 1:
Error += 'Link Join'
elif s == 2:
Error += 'Link NoIP'
elif s == -1:
Error += 'Link Fail'
elif s == -2:
Error += 'NoNet'
elif s == -3:
Error += 'BadAuth'
else:
Error += 'Unknown'
print(Error)
return
############################################################################
# Try to Connect to WiFi, returns WLAN status
############################################################################
def connect_to_Network():
print('Connecting to Network ...')
wlan.active(True)
wlan.config(pm = 0xa11140) # Disable power-save mode
wlan.connect(ssid, pw)
max_wait = 10 # wait 10 seconds to connect
while max_wait > 0:
if wlan.status() < 0 or wlan.status() >= 3:
break
max_wait -= 1
time.sleep(1)
status = wlan.status()
if status == 3:
wlan.ifconfig((host, '255.255.255.0', gateway, '8.8.8.8'))
status = wlan.ifconfig()
print('ip = ' + status[0])
return 1
else:
connect_Fail(status)
return 0
############################################################################
# Main
############################################################################
Onboard_LED.on()
try:
if check_SSID():
if connect_to_Network() == 1:
count = 5
Exit = False
s = socket.socket()
print('Connecting to {}:{}'.format(server,port))
s.connect((server, port))
while not Exit:
'''
get some data to send, read sensor etc
'''
data = ''some data
s.send(data)
msg = s.recv(512)
if msg.find(b'Success') == -1:
count += 1
if count == 5:
Exit = True
else:
print('Success')
s.close()
else:
print('Cannot connect ... ')
else:
print('Network NOT found ... ')
except Exception as e:
print('Error occurred : {}'.format(e))
wlan.disconnect()
time.sleep(0.1)
wlan.active(False)
time.sleep(0.1)
print('Disconnect from Network.')
print('')
Onboard_LED.off()
time.sleep(120)
############################################################################
Access Point File
############################################################################
# Pi Pico W Access Point
#
# Connects to Local WiFi to get Date Time if available
# Setup Pico as Access Point
# Listen for client communications
# Reply 'success' if data received ok
#
############################################################################
import network
import socket
import time
import ntptime
import uasyncio as asyncio
from machine import RTC
from SSID import SSID
from SSID_AP import SSID_AP
############################################################################
'''
SSID.py & SSID_AP.py are two files in the same folder as the running program
They contain SSID and Password information
SSID File: SSID.py
SSID = {
'ssid': 'Local WiFi Name',
'pw': 'Local Password'
}
SSID_AP File: SSID_AP.py
SSID_AP = {
'ssid': 'any name you want to call the access point',
'pw': 'whatever password you decide to use'
}
'''
############################################################################
# Local WiFi
server = '192.168.1.2'
gateway = '192.168.1.1'
port = 80
ssid = SSID['ssid']
pw = SSID['pw']
# HotSpot
serverAP = '192.168.10.1'
gatewayAP = '192.168.10.1'
portAP = 5263
ssidAP = SSID_AP['ssid']
pwAP = SSID_AP['pw']
############################################################################
# Setup
############################################################################
Onboard_LED = Pin("LED", Pin.OUT, value=0)
dt = RTC()
############################################################################
# Check for Server active
############################################################################
def check_SSID(wlan):
print('Checking for Network ...',ssid)
networks = wlan.scan()
found = False
for w in networks:
if w[0].decode() == ssid:
found = True
return found
############################################################################
# Display Connect Error
############################################################################
def connect_Fail(s):
Error = 'Connect Fail: '
if s == 0:
Error += 'Link Down'
elif s == 1:
Error += 'Link Join'
elif s == 2:
Error += 'Link NoIP'
elif s == -1:
Error += 'Link Fail'
elif s == -2:
Error += 'NoNet'
elif s == -3:
Error += 'BadAuth'
else:
Error += 'Unknown'
print(Error)
return
############################################################################
# Try to Connect to WiFi, returns WLAN status
############################################################################
def connect_to_Network(wlan):
print('Connecting to Network ...')
wlan.active(True)
wlan.config(pm = 0xa11140) # Disable power-save mode
wlan.connect(ssid, pw)
max_wait = 10 # wait 10 seconds to connect
while max_wait > 0:
if wlan.status() < 0 or wlan.status() >= 3:
break
max_wait -= 1
time.sleep(1)
status = wlan.status()
if status == 3:
wlan.ifconfig((server, '255.255.255.0', gateway, '8.8.8.8'))
status = wlan.ifconfig()
print('ip = ' + status[0])
return 1
else:
connect_Fail(status)
return 0
############################################################################
# Get time from NTP Server and adjust for day light saving
# Maybe there is a better way to do this.
############################################################################
def Get_NTPTime():
try:
print('Getting NTPTime ...')
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
time.sleep(2)
if check_SSID(wlan):
if connect_to_Network(wlan) == 1:
ntptime.settime()
# adjust for day light saving, remove if not daily saving time
s = time.time()
if dt.datetime()[1] in [10,11,12,1,2,3]:
s += 39600
else:
s += 36000
x = time.localtime(s)
dt.datetime((x[0],x[1],x[2],x[6],x[3],x[4],x[5],0))
time.sleep(0.2)
t = '{:02d}/{:02d}/{} {:02d}:{:02d}'.format(dt.datetime()[2],dt.datetime()[1],dt.datetime()[0],
dt.datetime()[4],dt.datetime()[5])
print(t)
time.sleep(2)
else:
print('Network NOT found ... ')
else:
print('SSID NOT found ... ')
wlan.disconnect()
time.sleep(0.1)
wlan.active(False)
time.sleep(4)
lcd.clear()
except Exception as e:
print('Error occurred : {}'.format(e))
'''
time.localtime()
0 1 2 3 4 5 6 7
(year, month, day, hour, minute, second, weekday, yearday)
dt.dt.datetime()
0 1 2 3 4 5 6 7
(year, month, day, weekday, hour, minute, second, subsecond)
Note: different location of weekday
'''
############################################################################
# Get Remote data, runs independant of Main Loop
############################################################################
async def SensorData(reader, writer):
print("Client connected")
Sensor = await reader.read(512) # returns all charaters including b''
Sensor = str(Sensor) # convert bytes object to str object
Sensor = Sensor[2:] # strip leading b'
Sensor = Sensor[:-1] # strip trailing '
'''
Do something with data received
'''
writer.write(b'Success') # send msg back
await writer.drain()
await writer.wait_closed()
print("Client disconnected")
#############################################################################
# Main Loop
#############################################################################
async def main():
# start server monitor task
asyncio.create_task(asyncio.start_server(SensorData, "0.0.0.0", portAP))
print('Server listening on {}:{}'.format(serverAP,portAP))
# Main loop
while True:
'''
Do stuff
'''
await asyncio.sleep(5) # need to wait some time to allow server task to function
############################################################################
# Startup
############################################################################
Get_NTPTime() # try to set the Pico time to correct local time
try:
print('Setting up AP ...')
time.sleep(2)
wlanAP = network.WLAN(network.AP_IF)
wlanAP.config(ssid=ssidAP, password=pwAP)
wlanAP.active(True)
print('ssid = ',ssidAP)
time.sleep(1)
wlanAP.ifconfig((serverAP, '255.255.255.0', gatewayAP, '8.8.8.8'))
time.sleep(0.1)
print('Config = ',wlanAP.ifconfig())
time.sleep(2)
asyncio.run(main())
except Exception as e:
print('Error occurred : {}'.format(e))
finally:
asyncio.new_event_loop()
wlanAP.disconnect()
time.sleep(0.1)
wlanAP.active(False)
time.sleep(0.1)
Onboard_LED.off()
############################################################################
############################################################################
````Preformatted text`
