Datasheet

102
4337K–USB–04/08
AT89C5130A/31A-M
20. Two Wire Interface (TWI)
This section describes the 2-wire interface. The 2-wire bus is a bi-directional 2-wire serial com-
munication standard. It is designed primarily for simple but efficient integrated circuit (IC) control.
The system is comprised of two lines, SCL (Serial Clock) and SDA (Serial Data) that carry infor-
mation between the ICs connected to them. The serial data transfer is limited to 400 Kbit/s in
standard mode. Various communication configuration can be designed using this bus. Figure
20-1 shows a typical 2-wire bus configuration. All the devices connected to the bus can be mas-
ter and slave.
Figure 20-1. 2-wire Bus Configuration
SCL
SDA
device2device1 deviceNdevice3
...