ESP-NOW

案例程序

ESP-NOW Master

主机通过扫描指定SSID的AP获取从机的mac地址, 然后添加到配对列表中。在主循环中执行数据发送。

from m5stack import *
from m5ui import *
from uiflow import *
from libs.m5_espnow import M5ESPNOW
import time

setScreenColor(0x222222)

flag_cb = None
slave_mac = None
slave_data = None
run = None
cnt_succes = None
count_send = None
peer_mac = None
slave_ssid = None

now = M5ESPNOW()

title0 = M5Title(title="ESPNOW-MASTER", x=100, fgcolor=0xFFFFFF, bgcolor=0xff0000)
label0 = M5TextBox(24, 75, "SLAVE MAC:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label1 = M5TextBox(125, 38, "label1", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label2 = M5TextBox(24, 109, "SEND COUNT:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label9 = M5TextBox(230, 219, "STOP", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label3 = M5TextBox(126, 75, "label3", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label10 = M5TextBox(24, 175, "REVC COUNT:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label4 = M5TextBox(25, 38, "SLAVE SSID:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label11 = M5TextBox(145, 175, "label11", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label5 = M5TextBox(146, 109, "label5", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label6 = M5TextBox(48, 219, "SEND", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label7 = M5TextBox(24, 144, "SUCCESS COUNT:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label8 = M5TextBox(174, 144, "label8", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)

peer_mac = None

def send_cb(flag):
  global flag_cb,slave_mac,slave_data,run,cnt_succes,count_send,peer_mac,slave_ssid
  flag_cb = flag
  if flag_cb:
    cnt_succes = cnt_succes + 1
    label8.setText(str(cnt_succes))

  pass


def recv_cb(dummy):
  global flag_cb,slave_mac,slave_data,run,cnt_succes,count_send,peer_mac,slave_ssid
  slave_mac, slave_data = now.espnow_recv_str()
  label11.setText(str(slave_data))

  pass

def buttonA_wasPressed():
  global flag_cb, slave_mac, slave_data, run, cnt_succes, count_send, peer_mac, slave_ssid
  run = 1
  pass
btnA.wasPressed(buttonA_wasPressed)

def buttonC_wasPressed():
  global flag_cb, slave_mac, slave_data, run, cnt_succes, count_send, peer_mac, slave_ssid
  run = 0
  pass
btnC.wasPressed(buttonC_wasPressed)

now.espnow_init(1, 1)
count_send = 0
cnt_succes = 0
flag_cb = 0
run = 0
slave_ssid = 'M5_Slave'
while peer_mac == None:
  peer_mac = now.espnow_scan(1, slave_ssid)
label1.setText(str(slave_ssid))
label3.setText(str(peer_mac))
now.espnow_add_peer(peer_mac, 1, 0, False)
now.espnow_send_cb(send_cb)
now.espnow_recv_cb(recv_cb)
while True:
  if run:
    count_send = count_send + 1
    now.espnow_send_data(1, str(count_send))
    label5.setText(str(count_send))
    wait_ms(1)
  wait_ms(2)

ESP-NOW Slave

从机开启指定名称的AP热点(提供主机发现并获取mac地址使用), 在接收回调中获取发送者的mac地址和数据, 发送返回相同数据。

from m5stack import *
from m5ui import *
from uiflow import *
from libs.m5_espnow import M5ESPNOW


setScreenColor(0x222222)
mac_addr = None
data = None
onetime = None
ssid = None

now = M5ESPNOW()

title0 = M5Title(title="ESPNOW-SLAVE", x=105, fgcolor=0xFFFFFF, bgcolor=0xff7c00)
label0 = M5TextBox(26, 82, "MAC ADDR:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label1 = M5TextBox(76, 47, "label1", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label2 = M5TextBox(26, 119, "REMOTE MAC:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label3 = M5TextBox(126, 82, "label3", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label4 = M5TextBox(26, 47, "SSID:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label5 = M5TextBox(150, 119, "label5", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label7 = M5TextBox(26, 159, "REMOTE DATA:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label8 = M5TextBox(157, 159, "label8", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label6 = M5TextBox(26, 195, "SEND DATA:", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)
label9 = M5TextBox(133, 195, "label9", lcd.FONT_Ubuntu, 0xFFFFFF, rotate=0)

def recv_cb(dummy):
  global mac_addr,data,onetime,ssid
  mac_addr, data = now.espnow_recv_str()
  label5.setText(str(mac_addr))
  label8.setText(str(data))
  label9.setText(str(data))
  if onetime:
    now.espnow_add_peer(mac_addr, 1, 1, False)
    now.espnow_recv_cb(recv_cb)
    onetime = 0
  now.espnow_send_data(1, data)

  pass

now.espnow_init(1, 1)
onetime = 1
ssid = 'M5_Slave'
now.espnow_set_ap(ssid, '')
label1.setText(str(ssid))
label3.setText(str(now.espnow_get_mac(0)))
now.espnow_recv_cb(recv_cb)

功能说明

from libs.m5_espnow import M5ESPNOW
now = M5ESPNOW()
now.espnow_init(ch, type)

• 初始化ESP-NOW到某一信道, 同时配置数据类型:
  • ch:0-13
  • type:
    • list: 0
    • string: 1

now.espnow_add_peer('', 1, 0, False)

• 添加配对设备, 并映射指定id:
  • peer: 设备mac地址
  • id：0-10
  • ifidx:s
    • ESP_IF_WIFI_STA:0
    • ESP_IF_WIFI_AP:1
  • encrypt:启用加密则需填入LMK

now.espnow_send_data(1, "Hello")

• 发送数据给已添加到配对列表中的id设备

def send_cb(flag):
  global flag_cb
  flag_cb = flag
  pass

now.espnow_send_cb(send_cb)

• 数据发送callback:
  • flag: 发送状态标志位
    • 发送成功:1
    • 发送失败:0

now.espnow_broadcast_data('1234')

• 广播发送数据

def recv_cb(dummy):
  slave_mac, slave_data = now.espnow_recv_str()
  print(str(slave_data))
  pass

now.espnow_recv_cb(recv_cb)

• 数据接收callback

now.espnow_get_mac(0)

• 获取本机mac地址

peer_mac = now.espnow_scan(1, slave_ssid)

• 扫描指定AP SSID, 并获得其mac地址。该功能常用于发现和添加新的设备。

now.espnow_set_ap(ssid, '')

• 启用AP热点, 并指定SSID和PASSWORD

now.espnow_set_pmk('')

• 若在添加配对设备时候启用了encrypt, 双方设备再可通过设置一致的PMK(Primary Master Key), 对LMK进行AES-128加密, 来实现加密通信, 未设置则使用默认值。

now.espnow_deinit()

• 逆初始化, 释放ESP-NOW。