LC01707PLF

No.A1928-9/18

Communication specification

Communication specifications are indicated as below:

Serial Interface (I

Sending and receiving data through I

line (SCL). This bus enables 8-bit bi-directional serial data to transmit at the maximum speed of 400kbits (fast mode).

This is not compatible with Hs mode.

Terms used in I

The following terms are used in I

Terms

Description

Transmitter

Device to send data to the bus

Receiver

Device to receive from the bus

Master

Device to start data transmission, generate signal, and terminate data transmission

Slave

Device of which address is designated master

[Start] and [Stop] conditions

[Start] condition is required at the start of data communication and [Stop] condition at the end of data communication.

The condition in which the SDA line changes from [H] to [L] with SCL at [H] is called the [Start] condition. The

condition in which the SDA line changes from [L] to [H] with SCL at [H] is called the [Start] condition.

Data transmission

The length of each byte which is output to SDA line is always 8 bits. An acknowledge bit is needed after each byte.

Data is transmitted sequentially from the most significant bit (MSB).

During the data transfer, the slave address is transmitted after the [Start] condition (S).

Data transfer is always ended by the [Stop] condition (P) generated by the master.

D7

D6

D1

D0

P

Sr

1

2

7

Sr

or

P

S

or

Sr

8

9

12

3-8

9

SDA

SCL

ACK:acknowledgement

MSB

START or repeated

START condition

ACK signal from slave

Byte complate,

interrupt within slave

Clock line held low while

interrrupts are serviced

Clock pulse for ACK

Clock pulse for ACK

ACK signal from receiver

STOP or repeated

START condition

SDA

SCL

S

P

SDA

SCL

START condition

STOP condition