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3e3d7df Mar 16, 2017
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/*
* i2c_port_address_scanner
* Scans ports D0 to D7 on an ESP8266 and searches for I2C device. based on the original code
* available on Arduino.cc and later improved by user Krodal and Nick Gammon (www.gammon.com.au/forum/?id=10896)
* D8 throws exceptions thus it has been left out
*
*/
#include <Wire.h>
void setup() {
Serial.begin(115200);
while (!Serial); // Leonardo: wait for serial monitor
Serial.println("\n\nI2C Scanner to scan for devices on each port pair D0 to D7");
scanPorts();
}
uint8_t portArray[] = {16, 5, 4, 0, 2, 14, 12, 13};
//String portMap[] = {"D0", "D1", "D2", "D3", "D4", "D5", "D6", "D7"}; //for Wemos
String portMap[] = {"GPIO16", "GPIO5", "GPIO4", "GPIO0", "GPIO2", "GPIO14", "GPIO12", "GPIO13"};
void scanPorts() {
for (uint8_t i = 0; i < sizeof(portArray); i++) {
for (uint8_t j = 0; j < sizeof(portArray); j++) {
if (i != j){
Serial.print("Scanning (SDA : SCL) - " + portMap[i] + " : " + portMap[j] + " - ");
Wire.begin(portArray[i], portArray[j]);
check_if_exist_I2C();
}
}
}
}
void check_if_exist_I2C() {
byte error, address;
int nDevices;
nDevices = 0;
for (address = 1; address < 127; address++ ) {
// The i2c_scanner uses the return value of
// the Write.endTransmisstion to see if
// a device did acknowledge to the address.
Wire.beginTransmission(address);
error = Wire.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("Unknow error at address 0x");
if (address < 16)
Serial.print("0");
Serial.println(address, HEX);
}
} //for loop
if (nDevices == 0)
Serial.println("No I2C devices found");
else
Serial.println("**********************************\n");
//delay(1000); // wait 1 seconds for next scan, did not find it necessary
}
void loop() {
}