Add I2C1 example

Author: Heltec-Aaron-Lee

examples/ESP32/I2C1_Scanner/I2C1_Scanner.ino

@@ -0,0 +1,71 @@
+/* Heltec Automation I2C scanner example (also it's a basic example how to use I2C1)
+ *
+ * ESP32 have two I2C (I2C0 and I2C1) bus
+ *
+ * OLED is connected to I2C0, so if scan with Wire (I2C0), the return address should be 0x3C.
+ *
+ * If you need scan other device address in I2C1...
+ *		- Comment all Wire.***() codes;
+ * 		- Uncomment all Wire1.***() codes;
+ *
+ * I2C scan example and I2C1
+ *
+ * HelTec AutoMation, Chengdu, China
+ * 成都惠利特自动化科技有限公司
+ * www.heltec.org
+ *
+ * this project also realess in GitHub:
+ * https://github.com/HelTecAutomation/Heltec_ESP32
+ * */
+
+#include "Arduino.h"
+#include "heltec.h"
+
+void setup()
+{
+	Heltec.begin(true, false, true);
+	Wire.begin(SDA_OLED, SCL_OLED); //Scan OLED's I2C address via I2C0
+	//Wire1.begin(SDA, SCL);        //If there have other device on I2C1, scan the device address via I2C1
+}
+
+void loop()
+{
+	byte error, address;
+	int nDevices;
+
+	Serial.println("Scanning...");
+
+	nDevices = 0;
+	for(address = 1; address < 127; address++ )
+	{
+		Wire.beginTransmission(address);
+		error = Wire.endTransmission();
+
+//		Wire1.beginTransmission(address);
+//		error = Wire1.endTransmission();
+
+		if (error == 0)
+		{
+			Serial.print("I2C device found at address 0x");
+			if (address<16)
+			Serial.print("0");
+			Serial.print(address,HEX);
+			Serial.println("  !");
+
+			nDevices++;
+		}
+		else if (error==4)
+		{
+			Serial.print("Unknown error at address 0x");
+			if (address<16)
+				Serial.print("0");
+			Serial.println(address,HEX);
+		}
+	}
+	if (nDevices == 0)
+	Serial.println("No I2C devices found\n");
+	else
+	Serial.println("done\n");
+
+	delay(5000);
+}

src/heltec.cpp

@@ -117,4 +117,3 @@ void Heltec_ESP32::VextOFF(void) //Vext default OFF
 }
 
 Heltec_ESP32 Heltec;
-