Datasheet

825
SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
36.6.3 Interrupt
The TWI interface has an interrupt line connected to the Interrupt Controller. In order to handle interrupts, the
Interrupt Controller must be programmed before configuring the TWI.
36.7 Functional Description
36.7.1 Transfer Format
The data put on the TWD line must be 8 bits long. Data is transferred MSB first; each byte must be followed by an
acknowledgement. The number of bytes per transfer is unlimited (see Figure 36-4).
Each transfer begins with a START condition and terminates with a STOP condition (see Figure 36-3).
 A high-to-low transition on the TWD line while TWCK is high defines the START condition.
 A low-to-high transition on the TWD line while TWCK is high defines a STOP condition.
Figure 36-3. START and STOP Conditions
Figure 36-4. Transfer Format
36.7.2 Modes of Operation
The TWI has different modes of operations:
 Master transmitter mode
 Master receiver mode
 Multi-master transmitter mode
 Multi-master receiver mode
 Slave transmitter mode
 Slave receiver mode
These modes are described in the following sections.
Table 36-5. Peripheral IDs
Instance ID
TWI0 17
TWI1 18
TWD
TWCK
Start Stop
TWD
TWCK
Start Address R/W Ack Data Ack Data Ack Stop