投稿日　2024年2月22日

参考記事　
https://lang-ship.com/blog/work/m5stickc-esp32-bluetooth-shutter-1-0-4/

目的　ダイソーのスマートフォンシャッターリモコンは200円と安い。これを使って、ESP32のLEDを制御する。

使用機材　
　ESP-WROOM-32E
　ダイソー　スマホシャッターリモコン　LOT.0505CC
　LED　　　　 1個　(16番ピン)
　抵抗　150Ω　1個
　ブレッドボード
　ジャンパーワイヤー

使用方法
　スケッチはほとんど同じだが、ESP32で使えることと、アンドロイド用シャッターリモコンで使用できる。
　シャッターリモコンのボタンを押せば、ESP32の16番ピンにつながれたLEDが光る。

結果
　ライブラリーや先人のプログラムを完全に理解しているわけでないため、初めは訳が分からないが、なんとかなった。
　LEDの出力をリレーに変え、産業機器のスタートボタンにする予定。

//
// A BLE client example that is rich in capabilities.
// There is a lot new capabilities implemented.
// author unknown
// updated by chegewara
// updated by kenzoos
//
#include "BLEDevice.h"
// The remote service we wish to connect to.
static BLEUUID serviceUUID("1812");
static boolean doConnect = false;
static boolean connected = false;
static boolean doScan = false;
static BLEAdvertisedDevice* myDevice;

#define LED_BUILTIN 16 //追記

static void notifyCallback(
BLERemoteCharacteristic* pBLERemoteCharacteristic,
uint8_t* pData,
size_t length,
bool isNotify) {
Serial.print("Notify callback for characteristic ");
Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
Serial.print("(");
Serial.print(pBLERemoteCharacteristic->getHandle());
Serial.print(") of data length ");
Serial.print(length);
Serial.print(" data: ");
for (int i = 0; i < length; i++) {
Serial.printf("%02X ", pData[i]);
}
Serial.println();

if (pData[0] == 2) {
digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
delay(100); // wait for 2 second
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
delay(5);
Serial.println("LED on off ");
}
}
class MyClientCallback : public BLEClientCallbacks {
void onConnect(BLEClient* pclient) {
}
void onDisconnect(BLEClient* pclient) {
connected = false;
Serial.println("onDisconnect");
}
};
bool connectToServer() {
Serial.print("Forming a connection to ");
Serial.println(myDevice->getAddress().toString().c_str());
BLEClient* pClient = BLEDevice::createClient();
Serial.println(" - Created client");
pClient->setClientCallbacks(new MyClientCallback());
// Connect to the remove BLE Server.
pClient->connect(myDevice); // if you pass BLEAdvertisedDevice instead of address, it will be recognized type of peer device address (public or private)
Serial.println(" - Connected to server");
// Obtain a reference to the service we are after in the remote BLE server.
BLERemoteService* pRemoteService = pClient->getService(serviceUUID);
if (pRemoteService == nullptr) {
Serial.print("Failed to find our service UUID: ");
Serial.println(serviceUUID.toString().c_str());
pClient->disconnect();
return false;
}
Serial.println(" - Found our service");
std::map* mapCharacteristics = pRemoteService->getCharacteristicsByHandle();
for (std::map::iterator i = mapCharacteristics->begin(); i != mapCharacteristics->end(); ++i) {
if (i->second->canNotify()) {
Serial.println(" - Add Notify");
i->second->registerForNotify(notifyCallback);
}
}
connected = true;
return true;
}
//
// Scan for BLE servers and find the first one that advertises the service we are looking for.
//
class MyAdvertisedDeviceCallbacks : public BLEAdvertisedDeviceCallbacks {
//
// Called for each advertising BLE server.
//
void onResult(BLEAdvertisedDevice advertisedDevice) {
Serial.print("BLE Advertised Device found: ");
Serial.println(advertisedDevice.toString().c_str());
// We have found a device, let us now see if it contains the service we are looking for.
if (advertisedDevice.haveServiceUUID() && advertisedDevice.isAdvertisingService(serviceUUID)) {
BLEDevice::getScan()->stop();
myDevice = new BLEAdvertisedDevice(advertisedDevice);
doConnect = true;
doScan = true;
} // Found our server
} // onResult
}; // MyAdvertisedDeviceCallbacks
void setup() {
Serial.begin(9600);
Serial.println("Starting Arduino BLE Client application...");
BLEDevice::init("");
// Retrieve a Scanner and set the callback we want to use to be informed when we
// have detected a new device. Specify that we want active scanning and start the
// scan to run for 5 seconds.
BLEScan* pBLEScan = BLEDevice::getScan();
pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
pBLEScan->setInterval(1349);
pBLEScan->setWindow(449);
pBLEScan->setActiveScan(true);
pBLEScan->start(5, false);
pinMode(LED_BUILTIN, OUTPUT);
} // End of setup.
// This is the Arduino main loop function.
void loop() {
// If the flag "doConnect" is true then we have scanned for and found the desired
// BLE Server with which we wish to connect. Now we connect to it. Once we are
// connected we set the connected flag to be true.
if (doConnect == true) {
if (connectToServer()) {
Serial.println("We are now connected to the BLE Server.");
} else {
Serial.println("We have failed to connect to the server; there is nothin more we will do.");
}
doConnect = false;
}
// If we are connected to a peer BLE Server, update the characteristic each time we are reached
// with the current time since boot.
if (connected) {
} else if (doScan) {
BLEDevice::getScan()->start(0); // this is just eample to start scan after disconnect, most likely there is better way to do it in arduino
}
delay(1000); // Delay a second between loops.
} // End of loop