Reading and writing to the STCF05 registers through the I²C bus

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Doc ID 15047 Rev 1

7

Reading and writing to the STCF05 registers through

the I²C bus

7.1

Writing to a single register

Writing to a single register starts with a START bit followed by the 7-bit device address of the

operation. The master then waits for an acknowledgement from the STCF05. The 8-bit

address of the desired register is sent afterwards to the STCF05. It is also followed by an

acknowledge pulse. The last transmitted byte is the data that is going to be written into the

register. It is followed again by an acknowledge pulse from the STCF05. The master then

generates a STOP bit and the communication is over. The whole cycle is represented in

Figure 15.

7.2

Writing to multiple registers with incremental addressing

It would be unpractical to send several times the device address and the address of the

register when writing to multiple registers. The STCF05 supports writing to multiple registers

with incremental addressing. When data is written to a register, the register address is

automatically incremented (by one), and therefore the next data can be sent without

resending the device address and the register address (see Figure 16).

Figure 15.

Writing to a single register

S

T

A

R

T

DEVICE

ADDRESS

7 bits

A

C

K

W

R

I

T

E

M

S

B

L

S

B

R

/

W

A

C

K

ADDRESS OF

REGISTER

DATA

A

C

K

A

C

K

S

T

O

P

M

S

B

M

S

B

L

S

B

L

S

B

SDA LINE

S

T

A

R

T

DEVICE

ADDRESS

7 bits

A

C

K

W

R

I

T

E

M

S

B

L

S

B

R

/

W

A

C

K

ADDRESS OF

REGISTER

DATA

A

C

K

A

C

K

S

T

O

P

M

S

B

M

S

B

L

S

B

L

S

B

S

T

A

R

T

DEVICE

ADDRESS

7 bits

A

C

K

W

R

I

T

E

M

S

B

L

S

B

R

/

W

A

C

K

ADDRESS OF

REGISTER

DATA

A

C

K

A

C

K

S

T

O

P

M

S

B

M

S

B

L

S

B

L

S

B

SDA LINE