This exercise program Raspberry Pi Pico/MicroPython + ESP32-S (ESP-AT) as WiFi TCP client to remote control ESP32-DevKitC V4/MicroPython WiFi TCP server onboard LED.
In Client side:
ESP32-S is a wireless module based on ESP32. It's flashed with AT-command firmware ESP-AT. It's act as a WiFi co-processor. Raspberry Pi Pico/MicroPython send AT-command to ESP32-S via UART. Please note that for ESP32 flashed with ESP-AT: UART1 (IO16/IO17) is used to send AT commands and receive AT responses, connected to GP0/GP1 of Pico.
Pico GP15 connected to ESP32-S EN pin, to reset it in power up.
Pico GP16 is used control remote LED.
In Server side:
ESP32-DevKitC V4 (with ESP32-WROVER-E module)/MicroPython is programed as WiFi server, receive command from client to turn ON/OFF LED accordingly.
Connection:
Client side, mpyPico_ESP32S_remoteCli_.py run on Raspberry Pi Pico.
Server side, upyESP32_AP_RemoteSvr_.py run on ESP32-DevKitC V4.
import uos
import machine
import utime
"""
Raspberry Pi Pico/MicroPython + ESP32-S exercise
ESP32-S with AT-command firmware (ESP-AT):
---------------------------------------------------
AT version:2.1.0.0(883f7f2 - Jul 24 2020 11:50:07)
SDK version:v4.0.1-193-ge7ac221
compile time(0ad6331):Jul 28 2020 02:47:21
Bin version:2.1.0WROM-3)
---------------------------------------------------
Pico send AT command to ESP32-S via UART,
Send command to server (ESP32/MicroPython)
to turn ON/OFF LED on server.
---------------------------------------------------
Connection:
powered by separated power supply
Pico ESP32-S
GND GND
GP0 (TX) (pin 1) IO16 (RXD)
GP1 (RX) (pin 2) IO17 (TXD)
GP15 (pin 20) EN
GP16 (pin 21) button
---------------------------------------------------
"""
#server port & ip hard-coded,
#have to match with server side setting
server_ip="192.168.4.1"
server_port=8000
network_ssid = "ESP32-ssid"
network_password = "password"
ESP_EN = 15
PIN_ESP_EN = machine.Pin(ESP_EN, machine.Pin.IN, machine.Pin.PULL_UP)
DIn = machine.Pin(16, machine.Pin.IN, machine.Pin.PULL_UP)
print()
print("Machine: \t" + uos.uname()[4])
print("MicroPython: \t" + uos.uname()[3])
#indicate program started visually
led_onboard = machine.Pin(25, machine.Pin.OUT)
led_onboard.value(0) # Toggle onboard LED
utime.sleep(0.5) # to indiacte program start
led_onboard.value(1)
utime.sleep(1)
led_onboard.value(0)
#Reset ESP
PIN_ESP_EN = machine.Pin(ESP_EN, machine.Pin.OUT)
PIN_ESP_EN.value(1)
utime.sleep(0.5)
PIN_ESP_EN.value(0)
utime.sleep(0.5)
PIN_ESP_EN.value(1)
PIN_ESP_EN = machine.Pin(ESP_EN, machine.Pin.IN, machine.Pin.PULL_UP)
uart = machine.UART(0, baudrate=115200)
print(uart)
RES_OK = b'OK\r\n'
len_OK = len(RES_OK)
RESULT_OK = '0'
RESULT_TIMEOUT = '1'
def sendCMD_waitResult(cmd, timeout=2000):
print("CMD: " + cmd)
uart.write(cmd)
prvMills = utime.ticks_ms()
result = RESULT_TIMEOUT
resp = b""
while (utime.ticks_ms()-prvMills)<timeout:
if uart.any():
resp = b"".join([resp, uart.read(1)])
resp_len = len(resp)
if resp[resp_len-len_OK:]==RES_OK:
print(RES_OK + " found!")
result = RESULT_OK
break
print("resp:")
try:
print(resp.decode())
except UnicodeError:
print(resp)
return result
#to make it simple to detect, RMCMD & RMSTA designed same length
#Remote Command from client to serve
RMCMD_len = 6
RMCMD_ON = "LEDONN" #turn LED ON
RMCMD_OFF = "LEDOFF" #turn LED OFF
#Remote status from server to client
RMSTA_len = 6
RMSTA_timeout = "timeout" #time out without/unknown reply
RMSTA_LEDON = "LedOnn"
RMSTA_LEDOFF = "LedOff"
"""
#Expected flow to send command to wifi is:
Pico (client) to ESP-01S response from ESP-01S to Pico
AT+CIPSEND=<cmd len>\r\n
AT+CIPSEND=<cmd len>\r\n
OK\r\n
>\r\n
<cmd>
Recv x bytes\r\n
SEND OK\r\n ---> ESP (server)
<--- ESP (server) end with OK\r\n
+IPD,10:<RMSTA>OK\r\n
+IPD,2:\r\n
"""
def sendRemoteCmd(rmcmd, timeout=2000):
result = RMSTA_timeout
if sendCMD_waitResult('AT+CIPSEND=' + str(len(rmcmd)) + '\r\n', timeout)==RESULT_OK:
#dummy read '>'
while not uart.any():
pass
print(uart.read(1))
print("Remote CMD: " + rmcmd)
if sendCMD_waitResult(rmcmd) == RESULT_OK:
endMills = utime.ticks_ms() + timeout
resp = b""
while utime.ticks_ms()<endMills:
if uart.any():
resp = b"".join([resp, uart.read(1)])
resp_len = len(resp)
if resp[resp_len-len_OK:]==RES_OK:
print(RES_OK + " found!")
rmSta=resp[resp_len-len_OK-RMSTA_len:resp_len-len_OK]
strRmSta=rmSta.decode() #convert bytes to string
print(strRmSta)
if strRmSta == RMSTA_LEDON:
result = strRmSta
elif strRmSta == RMSTA_LEDOFF:
result = strRmSta
break
print("resp:")
try:
print(resp.decode())
except UnicodeError:
print(resp)
return result
def sendCMD_waitResp(cmd, timeout=2000):
print("CMD: " + cmd)
uart.write(cmd)
waitResp(timeout)
print()
def waitResp(timeout=2000):
prvMills = utime.ticks_ms()
resp = b""
while (utime.ticks_ms()-prvMills)<timeout:
if uart.any():
resp = b"".join([resp, uart.read(1)])
print("resp:")
try:
print(resp.decode())
except UnicodeError:
print(resp)
"""
everytimes send command to server:
- join ESP32 network
- connect to ESP32 socket
- send command to server and receive status
"""
def connectRemoteSendCmd(cmdsend):
clearRxBuf()
print("join wifi network: " + "ESP32-ssid")
while sendCMD_waitResult('AT+CWJAP="' + network_ssid + '","'
+ network_password + '"\r\n') != RESULT_OK:
pass
sendCMD_waitResp('AT+CIFSR\r\n') #Obtain the Local IP Address
sendCMD_waitResult('AT+CIPSTATUS\r\n')
print("wifi network joint")
print("connect socket")
if sendCMD_waitResult('AT+CIPSTART="TCP","'
+ server_ip
+ '",'
+ str(server_port) + '\r\n', timeout=5000) == RESULT_OK:
sendCMD_waitResult('AT+CIPSTATUS\r\n')
print("RMST: " + sendRemoteCmd(rmcmd=cmdsend))
clearRxBuf()
sendCMD_waitResult('AT+CIPSTATUS\r\n')
sendCMD_waitResult('AT+CWQAP\r\n')
def clearRxBuf():
print("--- clear Rx buffer ---")
buf = b""
while uart.any():
buf = b"".join([buf, uart.read(1)])
print(buf)
print("-----------------------")
led_onboard.value(0)
clearRxBuf()
sendCMD_waitResult('AT\r\n') #Test AT startup
sendCMD_waitResult('AT+CWMODE=1\r\n') #Set the Wi-Fi mode 1 = Station mode
sendCMD_waitResult('AT+CIPMUX=0\r\n') #single connection.
led_onboard.value(1)
connectRemoteSendCmd(cmdsend=RMCMD_ON)
utime.sleep(1)
connectRemoteSendCmd(cmdsend=RMCMD_OFF)
#fast toggle led 5 times to indicate startup finished
for i in range(5):
led_onboard.value(0)
utime.sleep(0.2)
led_onboard.value(1)
utime.sleep(0.2)
led_onboard.value(0)
print("Started")
print("waiting for button")
#read digital input every 10ms
dinMills = utime.ticks_ms() + 30
prvDin = 1
debounced = False
while True:
if utime.ticks_ms() > dinMills:
dinMills = utime.ticks_ms() + 30
curDin = DIn.value()
if curDin != prvDin:
#Din changed
prvDin = curDin
debounced = False
else:
if not debounced:
#DIn changed for > 30ms
debounced = True
if curDin:
connectRemoteSendCmd(cmdsend=RMCMD_OFF)
else:
connectRemoteSendCmd(cmdsend=RMCMD_ON)
import utime
import uos
import network
import usocket
from machine import Pin
"""
ESP32/MicroPython exercise:
ESP32 act as Access Point,
and setup a simple TCP server
receive command from client and turn ON/OFF LED,
and send back status.
"""
ssid= "ESP32-ssid"
password="password"
led=Pin(13,Pin.OUT)
print("----- MicroPython -----")
for u in uos.uname():
print(u)
print("-----------------------")
for i in range(3):
led.on()
utime.sleep(0.5)
led.off()
utime.sleep(0.5)
ap = network.WLAN(network.AP_IF) # Access Point
ap.config(essid=ssid,
password=password,
authmode=network.AUTH_WPA_WPA2_PSK)
ap.config(max_clients=1) # max number of client
ap.active(True) # activate the access point
print(ap.ifconfig())
print(dir(ap))
mysocket = usocket.socket(usocket.AF_INET, usocket.SOCK_STREAM)
mysocket.setsockopt(usocket.SOL_SOCKET, usocket.SO_REUSEADDR, 1)
port = 8000
mysocket.bind(('',8000))
print("bind: " + str(port))
mysocket.listen(1)
#tomake it simple to detect, RMCMD & RMSTA designed same length
#Remote Command from client to serve
RMCMD_len = 6
RMCMD_ON = "LEDONN" #turn LED ON
RMCMD_OFF = "LEDOFF" #turn LED OFF
#Remote status from server to client
RMSTA_len = 6
RMSTA_timeout = "timeout" #time out without/unknown reply
RMSTA_LEDON = "LedOnn"
RMSTA_LEDOFF = "LedOff"
while True:
conn, addr = mysocket.accept()
print('Connected from: %s' % str(addr))
print()
request = conn.recv(1024)
print('request: %s' % str(request))
print()
strRqs = request.decode()
print("strRqs: "+strRqs)
if strRqs==RMCMD_ON:
conn.send(RMSTA_LEDON+'OK\r\n')
led.on()
elif strRqs==RMCMD_OFF:
conn.send(RMSTA_LEDOFF+'OK\r\n')
led.off()
else:
#unknown command
conn.send(request.upper())
conn.send('\r\n')
conn.close()
No comments:
Post a Comment