1602(I2C) Scanner

掃描I2C位址

0x27是LCD預設位址

每個裝置有不同位址

#include <Wire.h>

void setup()
{
Serial.begin (115200);
Wire.begin (21, 22); // sda=GPIO_21, scl=GPIO_22
}

void Scanner ()
{
Serial.println ();
Serial.println ("I2C scanner. Scanning ...");
byte count = 0;

Wire.begin();
for (byte i = 8; i < 120; i++)
{
Wire.beginTransmission (i); // Begin I2C transmission Address (i)
if (Wire.endTransmission () == 0) //0=success(ACK response)
{
Serial.print ("Found address: ");
Serial.print (i, DEC);
Serial.print (" (0x");
Serial.print (i, HEX); // PCF8574 7 bit address
Serial.println (")");
count++;
}
}
Serial.print ("Found ");
Serial.print (count, DEC); // numbers of devices
Serial.println (" device(s).");
}

void loop()
{
Scanner ();
delay (5000);
}

模擬器
https://wokwi.com/projects/340305156354605652