How To Send An 8-bit Address Over I2C - Arduino Forum Home » Arduino I2c 7 Bit Address » How To Send An 8-bit Address Over I2C - Arduino Forum Maybe your like Arduino I2c 8 Bit Address Arduino I2c Chat Arduino I2c Eeprom Example Code Arduino I2c Io Expander Code Arduino I2c Lcd1602 Example How to send an 8-bit address over I2C Projects Programming SidA30 June 16, 2017, 1:40pm 1 Hello all, My question is rather simple, I am trying to talk to a device which has an 8-Bit address. I cannot find I2C code to send an 8-Bit address, only 7-Bit. Wire.beginTransmission(adress); ^ Only sends an 7 bit. I'll show you my code, I am basically sending an 8-bit address and then sending 8 bytes of data. Then I send an 8-Bit address and read 12 bytes of data. I have made the code as basic as possible. p.s - I'm using an oscilloscope to monitor the bits, that's why there is delays in the code, just so I know where I am. Any help would be greatly appreciated. Code Below. #include <Wire.h> byte Values[12]; void setup() { Wire.begin(); Serial.begin(9600); } void loop() { delay(3); Wire.beginTransmission(202); for (byte i = 0; i <= 7; i++) { Wire.write(0x00); } Wire.endTransmission(); delay(1); Wire.requestFrom(203, 12); if (Wire.available() > 0) { Serial.println("We are Reading!"); for (byte i = 0; i <= 11; i++) { Values = Wire.read(); }* Wire.endTransmission();* }* } 1 Like oqibidipo June 16, 2017, 5:10pm 2 Divide the address by 2. Use 101 for both beginTransmission() and requestFrom(). Wire - Arduino Reference The Arduino programming language Reference, organized into Functions, Variable and Constant, and Structure keywords. There are both 7- and 8-bit versions of I2C addresses. 7 bits identify the device, and the eighth bit determines if it's being written to or read from. The Wire library uses 7 bit addresses throughout. If you have a datasheet or sample code that uses 8 bit address, you'll want to drop the low bit (i.e. shift the value one bit to the right), yielding an address between 0 and 127. 6v6gt June 16, 2017, 5:14pm 3 Probably the 8 bit address you have got for the slave device is a 7 bit address with binary '0' at the end for reading and a '1' at the end for writing. Link. Try using the decimal value of 65 for both reading and writing to the device to see if you get anywhere. Maybe you can also load the I2C scanner sketch and see what device addresses are reported. Otherwise, provide a link here to the device you are attempting to connect to. Related topics Topic Replies Views Activity I2C addressing Networking, Protocols, and Devices 4 1637 May 6, 2021 I2C - 8-bits Slave address Networking, Protocols, and Devices 6 4692 May 6, 2021 I2C bus Networking, Protocols, and Devices 4 2215 May 6, 2021 Possible Wire library doc error Bugs & Suggestions 4 1498 May 6, 2021 Wire.write 8bit byte Programming 29 6739 January 18, 2022 Tag » Arduino I2c 7 Bit Address I2C Addressing, Registers, And Bits - Arduino Forum Wire - Arduino Reference Still Trying To Understand I2C Addressing. - Arduino Forum How To Scan I2C Address In Arduino A Guide To Arduino & The I2C Protocol (Two Wire) I2C - 8-bits Slave Address - Arduino Forum How To Find I2C Address Using Arduino Arduino I2C - ElectronicWings I2C: 7 Or 8 Bit Addresses? [Fixed! Pull Request Submitted.] I2C Tutorial - Robot Electronics 7 Bit 8 Bit And 10 Bit I2C Slave Addressing - Total Phase 4. Getting Started With I2C on The Arduino - Tech Explorations The List | I2C Addresses! | Adafruit Learning System