This page is to Scan I2C by Arduino and ESP8266
Hardware and Software
Hardware
Arduino and any I2C Devices Connected
Software
Arduino IDE
Scan I2C Address
THIS IS OLED 0.9 and 1.3 inch I2C Address
CHANGING I2C ADDRESSES:
SOME I2C interfaces have pins (or solder pads) that can be changed to change the address. They are usually labelled A0-A1-A2 . Here's the way addresses change from a default 0x27 with if you connect address pads together.
(1 = Not Connected. 0 = Connected):
EEPROM AT24C512 :
I2C scanner. Scanning ...
Found address: 81 (0x51)
This example is ..........
I2C scanner. Scanning ... Found address: 39 (0x27) Done. Found 1 device(s).
Scan I2S on ESP8266
-- http://www.esp8266.com/viewtopic.php?f=19&t=771
-- Scan for I2C devices
id=0
sda=8
scl=9
-- initialize i2c, set pin1 as sda, set pin0 as scl
i2c.setup(id,sda,scl,i2c.SLOW)
for i=0,127 do
i2c.start(id)
resCode = i2c.address(id, i, i2c.TRANSMITTER)
i2c.stop(id)
if resCode == true then print("We have a device on address 0x" .. string.format("%02x", i) .. " (" .. i ..")") end
end
// I2C Scanner // Written by Nick Gammon // Date: 20th April 2011 #include <Wire.h> void setup() { Serial.begin (115200); // Leonardo: wait for serial port to connect while (!Serial) { } Serial.println (); } // end of setup void loop() {Serial.println ("I2C scanner. Scanning ..."); byte count = 0; Wire.begin(); for (byte i = 8; i < 120; i++) { Wire.beginTransmission (i); if (Wire.endTransmission () == 0) { Serial.print ("Found address: "); Serial.print (i, DEC); Serial.print (" (0x"); Serial.print (i, HEX); Serial.println (")"); count++; delay (1); // maybe unneeded? } // end of good response } // end of for loop Serial.println ("Done."); Serial.print ("Found "); Serial.print (count, DEC); Serial.println (" device(s)."); delay(2000); }