[[PageOutline]] = Inter-Integrated Circuit (I2C) = The Inter-Integrated Circuit by Philips is a popular interconnect (typically on-board) used on embedded processors as well as modern computers consisting of 2-wires (other than ground, power, and optional interrupts): * SCL - clock * SDA - data An I2C bus may be multi-master and support interrupts from the device to host controller. Reference: * http://en.wikipedia.org/wiki/I%C2%B2C == On-Board I2C Host Controllers == Various Gateworks boards support 3.3V TTL I2C to an off-board expansion connector: ||= Family =||= Board =||= Device =||= I2C Buffer Enable =||= Connector =|| || Newport || GW630x || TWSI1 /dev/i2c-1 || N/A || J14 (dedicated SDA/GND/SCL) || || || GW640x || TWSI1 /dev/i2c-1 || N/A || J14 (dedicated SDA/GND/SCL) || || || || Ventana || GW54xx-B+ || I2C3 /dev/i2c-2 || gpio101 || J16 (shared with DIO0/DIO1) ^^^1^^^ || || || GW53xx-B+ || I2C3 /dev/i2c-2 || gpio101 || J4 (shared with DIO0/DIO1) ^^^1^^^ || || || GW52xx-C+ || I2C3 /dev/i2c-2 || N/A || J4 (shared with DIO0/DIO1) ^^^1^^^ ^^^2^^^ || || || GW551x || I2C3 /dev/i2c-2 || N/A || J3 (dedicated SDA/SCL/GND) || 1. Ventana off-board I2C shares pins with MX6_DIO0 / MX6_DIO1 which need to be configured as inputs to use I2C 2. requires resistor loading option Please consult the ​Hardware Manuals for pinouts See also: * [wiki:ventana/DigitalIO#I2Csupport Ventana I2C] == USB I2C Host Controllers == A I2C master can also be added via USB expansion. For example: * [http://trac.gateworks.com/wiki/expansion/gw16113 GW16113 firmware-flexible USB 2.0 FS expansion] * [http://www.commell.com.tw/product/Peripheral/PCI%20Express%20mini%20card/MPX-24794S.HTM Commell MPX-24794S USB 2.0 FS SPI/I2C/GPIO expansion] == Linux Kernel API == See [wiki:linux/i2c]