NO:
W90P710 Programming Guide
VERSION:
2.0
PAGE:
199
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed, distributed or reproduced without permission
from Winbond.
Table No.: 2005-W90P710-11-A
17 I
2
C Synchronous Serial Interface Controller
17.1 Overview
The W90P710
I
2
C
includes two channels, I2C_0 and I2C_1, which 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.
8-bit oriented bi-directional serial data can transfers up to 100 kbit/s in Standard-mode, up to 400
kbit/s in the Fast-mode, or up to 3.4 Mbit/s in the High-speed mode. Only 100kbps and 400kbps
modes are supported directly. For High-speed mode special IOs are needed. If these IOs are
available and used, then High-speed mode is also supported.
Data is transferred between a Master and a Slave synchronously to SCL on the SDA line on a
byte-by-byte
basis. Each data byte is 8 bits long. There is one SCL clock pulse for each data bit with
the
MSB being transmitted first
. An acknowledge bit follows each transferred byte. Each bit is
sampled during the high period of SCL; therefore, the SDA line may be changed only during the low
period of SCL and must be held stable during the high period of SCL. A transition on the SDA line
while SCL is high is interpreted as a command (START or STOP).
The I
2
C Master Core includes the following features:
AMBA APB interface compatible
Compatible with Philips I
2
C standard, support master mode
Multi Master Operation
Clock stretching and wait state generation
Provide multi-byte transmit operation, up to 4 bytes can be transmitted in a single transfer
Software programmable acknowledge bit