4.6.6 Connecting to the I²C Interface

Four different FLEXCOM interfaces, with seven possible configurations (configured in TWI mode), and one pure TWI Interface are available on the ATSAMA5D27-WLSOM1 module.

The Flexible Serial Communication Controller (FLEXCOM) offers several serial communication protocols that are managed by the three submodules USART, SPI, and TWI.

The Two-wire Interface (TWI) interconnects components on a unique two-wire bus, made up of one clock line and one data line with speeds of up to 400 kbit/s in Fast mode and up to 3.4 Mbit/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), Dot Matrix/Graphic LCD Controller and temperature sensor. The TWI is programmable as a host or a client with sequential or single-byte access. Multiple host capability is supported.

Table 4-9. I²C Interface Configurations
Interface InstanceIO SetPin #PIOPin NameComment
TWI13120PD19TWD1No need of external pull-up.

Already integrated in ATSAMA5D27-WLSOM1 module

TWI13122PD20TWCK1
FLEXCOM0128PB28FLEXCOM0_IO0Need external pull-up in case

the FLEXCOM interface is used as an I²C/TWI interface.

FLEXCOM0127PB29FLEXCOM0_IO1
FLEXCOM21171PA6FLEXCOM2_IO0
FLEXCOM21173PA7FLEXCOM2_IO1
FLEXCOM22127PD26FLEXCOM2_IO0
FLEXCOM22123PD27FLEXCOM2_IO1
FLEXCOM3122PA15FLEXCOM3_IO0
FLEXCOM31175PA13FLEXCOM3_IO1
FLEXCOM3258PC20FLEXCOM3_IO0
FLEXCOM3263PC21FLEXCOM3_IO1
FLEXCOM4139PC28FLEXCOM4_IO0
FLEXCOM4138PC29FLEXCOM4_IO1
FLEXCOM42119PD12FLEXCOM4_IO0
FLEXCOM42116PD13FLEXCOM4_IO1