M5Stack同士でシリアル通信

今回は、M5Stack同しでシリアル通信をして、文字列を送信＆受信してみました

参考
http://robooptions.blog.fc2.com/blog-entry-9.html

この場合はM5StickCでしたが、M5Stackでやってみました。今はまだシリアル通信でしかできないけど、そのうち、CardKB(M5StackのGroveキーボード)やディスプレイ表示でやりたいです。

スレーブのBluetooth用MACアドレスを調べる
スレーブのM5Stackにこのコードを記述

void setup(void) {
  Serial.begin(115200);
  Serial.println("-----------------");
  uint8_t macBT[6];
  esp_read_mac(macBT, ESP_MAC_BT);
  Serial.printf("%02X:%02X:%02X:%02X:%02X:%02X\r\n", macBT[0], macBT[1], macBT[2], macBT[3], macBT[4], macBT[5]);
}

void loop() {
  delay(1000);
}

するとシリアルモニタに「1A:2B:3C:4D:5E:6F」のようなアドレスが出るのでこれを使って…

マスター側

//This example code is in the Public Domain (or CC0 licensed, at your option.)
//By Victor Tchistiak - 2019
//
//This example demostrates master mode bluetooth connection and pin
//it creates a bridge between Serial and Classical Bluetooth (SPP)
//this is an extention of the SerialToSerialBT example by Evandro Copercini - 2018
//

#include "BluetoothSerial.h"
#include <M5Stack.h>

BluetoothSerial SerialBT;

String MACadd = "1A:2B:3C:4D:5E:6F";//スレーブのアドレス
uint8_t address[6]  = {0x1A, 0x2B, 0x3C, 0x4D, 0x5E, 0x6F};//スレーブのアドレス
//uint8_t address[6]  = {0x00, 0x1D, 0xA5, 0x02, 0xC3, 0x22};
String name = "OBDII";
char *pin = "1234"; //<- standard pin would be provided by default
bool connected;

String History[10] = {"", "", "", "", "", "", "", "", "", ""};

void setup() {
  M5.begin();
  Serial.begin(115200);
  SerialBT.begin("ESP32test", true);
  Serial.println("The device started in master mode, make sure remote BT device is on!");
  M5.Lcd.setTextSize(3), M5.Lcd.setCursor(50, 80), M5.Lcd.print("Connected...");
  connected = SerialBT.connect(address);
  M5.Lcd.setTextSize(2);
  if (connected) {
    M5.Lcd.clear();
  } else {
    while (!SerialBT.connected(10000)) {
      M5.Lcd.clear();
      Serial.println("Failed to connect. Make sure remote device is available and in range, then restart app.");
      M5.Lcd.setTextColor(RED), M5.Lcd.setCursor(0, 80), M5.Lcd.print("Failed to connect");
    }
  }
  delay(3000);
  M5.Lcd.clear();
  M5.Lcd.setTextColor(WHITE), M5.Lcd.setTextSize(2), M5.Lcd.setCursor(0, 0);


  // disconnect() may take upto 10 secs max
  if (SerialBT.disconnect()) {
    Serial.println("Connected Succesfully!");
    M5.Lcd.setTextColor(GREEN), M5.Lcd.setCursor(0, 80), M5.Lcd.print("Connected Succesfully!");
  }
  //this would reconnect to the name(will use address, if resolved) or address used with connect(name / address).
  SerialBT.connect();
}

void loop() {
  if (Serial.available()) {
    String datastring = Serial.readStringUntil(';');
    Serial.print("SEND:" + datastring);
    add("SEND:" + datastring);
    SerialBT.print(datastring);
    //Serial.print("myself:");
    //Serial.print(Serial.readStringUntil(';'));

  }
  if (SerialBT.available()) {
    String datastring = SerialBT.readStringUntil(';');
    Serial.print("READ:" + datastring);
    add("READ:" + datastring);
  }
  delay(20);
}


void add(String addstring) {
  History[9] = History[8];
  History[8] = History[7];
  History[7] = History[6];
  History[6] = History[5];
  History[5] = History[4];
  History[4] = History[3];
  History[3] = History[2];
  History[2] = History[1];
  History[1] = History[0];
  History[0] = addstring;
  M5.Lcd.fillRect(0, 0, 320, 180, BLACK);
  M5.Lcd.setTextColor(WHITE), M5.Lcd.setTextSize(2), M5.Lcd.setCursor(0, 0);
  M5.Lcd.print(History[0]);
  M5.Lcd.print(History[1]);
  M5.Lcd.print(History[2]);
  M5.Lcd.print(History[3]);
  M5.Lcd.print(History[4]);
  M5.Lcd.print(History[5]);
  M5.Lcd.print(History[6]);
  M5.Lcd.print(History[7]);
  M5.Lcd.print(History[8]);
  M5.Lcd.print(History[9]);
  M5.Lcd.fillRect(0, 180, 100, 100, BLACK);
}

スレーブ側

//This example code is in the Public Domain (or CC0 licensed, at your option.)
//By Evandro Copercini - 2018
//
//This example creates a bridge between Serial and Classical Bluetooth (SPP)
//and also demonstrate that SerialBT have the same functionalities of a normal Serial

#include "BluetoothSerial.h"
#include <M5Stack.h>

String History[10] = {"", "", "", "", "", "", "", "", "", ""};
String sendstring = "";

#if !defined(CONFIG_BT_ENABLED) || !defined(CONFIG_BLUEDROID_ENABLED)
#error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
#endif

BluetoothSerial SerialBT;

void setup() {
  M5.begin();
  Serial.begin(115200);
  SerialBT.begin("ESP32test"); //Bluetooth device name
  Serial.println("The device started, now you can pair it with bluetooth!");
}

void loop() {
  if (Serial.available()) {
    String datastring = Serial.readStringUntil(';');
    Serial.print("SEND:" + datastring);
    add("SEND:" + datastring);
    SerialBT.print(datastring);
    //Serial.print("myself:");
    //Serial.print(Serial.readStringUntil(';'));

  }
  if (SerialBT.available()) {
    String datastring = SerialBT.readStringUntil(';');
    Serial.print("READ:" + datastring);
    add("READ:" + datastring);
  }
  delay(20);
}

void add(String addstring) {
  History[9] = History[8];
  History[8] = History[7];
  History[7] = History[6];
  History[6] = History[5];
  History[5] = History[4];
  History[4] = History[3];
  History[3] = History[2];
  History[2] = History[1];
  History[1] = History[0];
  History[0] = addstring;
  M5.Lcd.fillRect(0, 0, 320, 180, BLACK);
  M5.Lcd.setTextSize(2), M5.Lcd.setCursor(0, 0);

  for (byte i = 0; i = 9; i++) {
    if (History[i].charAt(0) == 'S'){
      M5.Lcd.setTextColor(WHITE);
    }else{
      M5.Lcd.setTextColor(YELLOW);
    }
    M5.Lcd.print(History[i]);
  }
}

動作すると、シリアルでの会話(SEND: READ:が出ます)や、M5Stackに過去の履歴の表示ができます。

バグ
・早く送信しまくるとバグる
・;(セミコロン)は送信不可(バグる)
・ディスプレイ表示▲