Atmel Xplained Evaluation Board AT32UC3A3-XPLD AT32UC3A3-XPLD 데이터 시트
제품 코드
AT32UC3A3-XPLD
444
32072H–AVR32–10/2012
AT32UC3A3
22. Two-wire Slave Interface (TWIS)
Rev.: 1.0.0.1
22.1
Features
•
Compatible with I
²
C standard
– Transfer speeds of 100 and 400 kbit/s
– 7 and 10-bit and General Call addressing
•
Compatible with SMBus standard
– Hardware Packet Error Checking (CRC) generation and verification with ACK response
– SMBALERT interface
– 25 ms clock low timeout delay
– 25 ms slave cumulative clock low extend time
•
Compatible with PMBus
•
DMA interface for reducing CPU load
•
Arbitrary transfer lengths, including 0 data bytes
•
Optional clock stretching if transmit or receive buffers not ready for data transfer
•
32-bit Peripheral Bus interface for configuration of the interface
22.2
Overview
The Atmel Two-wire Slave Interface (TWIS) 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, based on a
byte-oriented transfer format. It can be used with any Atmel Two-wire Interface bus, I²C, or
SMBus-compatible master. The TWIS is always a bus slave and can transfer sequential or sin-
gle bytes.
bus, made up of one clock line and one data line with speeds of up to 400 kbit/s, based on a
byte-oriented transfer format. It can be used with any Atmel Two-wire Interface bus, I²C, or
SMBus-compatible master. The TWIS is always a bus slave and can transfer sequential or sin-
gle bytes.
Below,
lists the compatibility level of the Atmel Two-wire Slave Interface and a full I²C
compatible device.
Note:
1. START + b000000001 + Ack + Sr
Table 22-1.
Atmel TWIS Compatibility with I²C Standard
I²C
Standard
Atmel TWIS
Standard-mode (100 kbit/s)
Supported
Fast-mode (400 kbit/s)
Supported
7 or 10 bits Slave Addressing
Supported
START BYTE
Not Supported
Repeated Start (Sr) Condition
Supported
ACK and NAK Management
Supported
Slope control and input filtering (Fast mode)
Supported
Clock stretching
Supported