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NUC126
Aug. 08, 2018
Page
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Rev 1.03
NUC12
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6.11 I
2
C Serial Interface Controller (I
2
C)
6.11.1
Overview
I
2
C is a two-wire, bi-directional serial bus that provides a simple and efficient method of data exchange
between devices. The I
2
C standard is a true multi-master bus including collision detection and
arbitration that prevents data corruption if two or more masters attempt to control the bus
simultaneously.
There are two sets of I
2
C controllers which support Power-down wake-up function.
6.11.2
Features
The I
2
C bus uses two wires (SDA and SCL) to transfer information between devices connected to the
bus. The main features of the I
2
C bus include:
Supports up to two I
2
C ports
Master/Slave mode
Bidirectional data transfer between masters and slaves
Multi-master bus (no central master)
Arbitration between simultaneously transmitting masters without corruption of serial data
on the bus
Serial clock synchronization allow devices with different bit rates to communicate via one
serial bus
Serial clock synchronization used as a handshake mechanism to suspend and resume
serial transfer
Built-in 14-bit time-out counter requesting the I
2
C interrupt if the I
2
C bus hangs up and
timer-out counter overflows
Programmable clocks allow for versatile rate control
Supports 7-bit addressing mode
Supports multiple address recognition ( four slave address with mask option)
Supports Power-down wake-up function
Supports PDMA with one buffer capability
Supports two-level buffer function
Supports setup/hold time programmable