I²C (Inter-Integrated Circuit, referred to as I-squared-C, I-two-C, or IIC) is a multimaster serial single-ended computer bus invented by Philips used for attaching low-speed peripherals to a motherboard, embedded system, cellphone, or other electronic device. Not to be confused with the term Two Wire Interface which only describes a compatible hardware interface.
Since the mid-1990s, several competitors (e.g., Siemens AG (later Infineon Technologies AG, now Intel mobile communications), NEC, Texas Instruments, STMicroelectronics (formerly SGS-Thomson), Motorola (later Freescale), Intersil, etc.) brought I²C products on the market, which are fully compatible with the NXP (formerly Philips' semiconductor division) I²C-system. Since October 10, 2006, no licensing fees are required to implement the I²C protocol. However, fees are still required to obtain I²C slave addresses allocated by NXP.
SMBus, defined by Intel in 1995, is a subset of I²C that defines the protocols more strictly. One purpose of SMBus is to promote robustness and interoperability. Accordingly, modern I²C systems incorporate policies and rules from SMBus, sometimes supporting both I²C and SMBus with minimal reconfiguration required.
I2C is a very important bus, we have more than ten products using the I2C interface.
The following table will help you find I2C addresses of Seeed products.
| Address | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | A | B | C | D | E | F |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0x0 | Xadow - Multichannel_Gas_Sensor Grove - Multichannel Gas Sensor |
Motor Driver | ||||||||||||||
| 0x1 | FM Receiver | H3LIS331DL | Q Touch | Compass 6 Axis Accel Compass 2.0 6 Axis Accel Compass |
||||||||||||
| 0x2 | Digital Light Sensor | |||||||||||||||
| 0x3 | Color Sensor | OLED96x96 OLED128x128 3 Axis Compass |
LCD RGB Backlight | |||||||||||||
| 0x4 | TH02 | MMA7660FC | ||||||||||||||
| 0x5 | ADXL345 NFC Tag |
ADC | Touch Sensor | Touch Sensor Digital Infrared Temp |
Touch Sensor | Touch Sensor | ||||||||||
| 0x6 | LCD RGB Backlight | RTC Gyro IMU 9DOF IMU 10DOF |
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| 0x7 | Gesture | HP206C | BMP085 BMP180 IMU 9DOF IMU 10DOF |