11.1.1 Interfacing in I²C/TWI Mode

Eleven Flexible Serial Communication Controller (FLEXCOM) interfaces configurable in Two-Wire Interface (TWI) mode, and one TWI interface, are available on the SAM9X60D1G-I/LZB.

The Two-Wire Interface (TWI) can interconnect with external components on a unique two-wire bus, made up of one clock line and one data line with speeds of up to 400 Kbits/s in Fast mode and up to 3.4 Mbits/s in High-Speed Client mode only, based on a byte-oriented transfer format.

It can be used with any Two-Wire Interface bus Serial EEPROM and I²C-compatible devices, such as a Real-Time Clock (RTC), a dot matrix/graphic LCD controller or a temperature sensor. The TWI is programmable as a host or a client with sequential or single-byte access. Multiple host capability is supported.

Table 11-1. I²C/TWI Interface Configurations
Interface InstanceIO SetPin No.PIOPin NameComment
FLEXCOM0121PA0FLEXCOM0_IO0_TWD_PA0No external pull-up needed. Already integrated in the SAM9X60D1G-I/LZB.
22PA1FLEXCOM0_IO1_TWCK_PA1
FLEXCOM1173PA5FLEXCOM1_IO0External pull-up needed in case the FLEXCOM interface is used as an I²C/TWI interface.
74PA6FLEXCOM1_IO1
FLEXCOM2132PA7FLEXCOM2_IO0
33PA8FLEXCOM2_IO1
FLEXCOM31120PC22FLEXCOM3_IO0
121PC23FLEXCOM3_IO1
FLEXCOM41145PA12FLEXCOM4_IO0
144PA11FLEXCOM4_IO1
FLEXCOM51, 235PA22FLEXCOM5_IO0
36PA21FLEXCOM5_IO1
FLEXCOM6180PA30FLEXCOM6_IO0
79PA31FLEXCOM6_IO1
FLEXCOM7192PC0FLEXCOM7_IO0
93PC1FLEXCOM7_IO1
FLEXCOM91102PC8FLEXCOM9_IO0
104PC9FLEXCOM9_IO1
FLEXCOM101111PC16FLEXCOM10_IO0
112PC17FLEXCOM10_IO1
FLEXCOM11164PB19FLEXCOM11_IO0
60PB20FLEXCOM11_IO1
FLEXCOM12161PB21FLEXCOM12_IO0
62PB22FLEXCOM12_IO1