NUTINY-SDK-M0516 Nuvoton Technology Corporation of America, NUTINY-SDK-M0516 Datasheet - Page 159

• Manufacturer Part Number: NUTINY-SDK-M0516
• Description: BOARD EVAL NUMICRO M051 SERIES
• Manufacturer: Nuvoton Technology Corporation of America
• Series: NuMicro M051™r
• Type: MCUr

Specifications of NUTINY-SDK-M0516

• Contents: Board, Cable
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: M051™ Series, M052/M054/M058/M0516

6.5.1
6.5.2
6.5 I2C Serial Interface Controller (Master/Slave)
NuMicro M051
I2C is a two-wire, bi-directional serial bus that provides a simple and efficient method of data
exchange between devices. The I2C 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.
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). Please refer to the Figure
6.5-1 for more detail I2C BUS Timing.
The device’s on-chip I2C provides the serial interface that meets the I2C bus standard mode
specification. The I2C port handles byte transfers autonomously. To enable this port, the bit ENS1
in I2CON should be set to '1'. The I2C H/W interfaces to the I2C bus via two pins: SDA (Px.y,
serial data line) and SCL (Px.y, serial clock line). Pull up resistor is needed for Pin Px.y and Px.y
for I2C operation as these are open drain pins. When the I/O pins are used as I2C port, user must
set the pins function to I2C in advance.
The I2C bus uses two wires (SDA and SCL) to transfer information between devices connected to
the bus. The main features of the bus are:
SDA
SCL
Overview
Features
Support Master and 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
STOP
t
BUF
START
t
HD;STA
™
t
LOW
Series Technical Reference Manual
Figure 6.5-1 I2C Bus Timing
t
HIGH
t
HD;DAT
- 159 -
t
r
Publication Release Date: Sept 14, 2010
t
f
t
SU;DAT
t
SU;STA
Repeated
START
Revision V1.2
t
SU;STO
STOP