Preliminary

TTP229

09’/12/22

Page 11 of 19

Ver : 1.1

For 8 input keys mode

from master

NOT ACK

from slave

ACK

Stop

Data_0

Start

Slave Address

B0

B1

B2

B3

B4

B5

B6

B7

R

A0

A1

A2

For 16 input keys mode

from master

NOT ACK

from master

ACK

from slave

ACK

Start

Slave Address

Data_0

Data_1

Stop

B0

B1

B2

B3

B4

B5

B6

B7

B0

B1

B2

B3

B4

B5

B6

B7

R

A0

A1

A2

Note : Data_0 : B7~B0 is TP0~TP7 on/off status. 0 is key off, 1 is key on.

Data_1 : B7~B0 is TP8~TP15 on/off status. 0 is key off, 1 is key on.

Figure 3-5-1. Read Operation Sequence

START

Condition

P

STOP condition

Change

Data

Data or

ACK Valid

SCL

S

SDA

Figure 3-5-2. Data Transmission Sequence

Condition

START

Condition

STOP

ACK

DATA

ACK

DATA

ACK

R/W

ADDRESS

S

P

9

98

8

1 - 7

1 - 7

9

8

1 - 7

SCL

SDA

Figure 3-5-3. A complete data transfer

BUF

t

SU;STO

r

t

r

t

t

HD;STA

t

SU;STA

t

f

t

f

t

SU;DAT

t

HIGH

t

HD;STA

t

HD;DAT

t

LOW

t

S

P

Sr

S

SCL

SDA