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POWER MANAGEMENT

SC900A

Applications Information (Cont.)

Stop Separated Reads

Another read format is available which is, in effect, an extension of the combined format read. This format allows a

master to set up the register address pointer for a read and return to that slave some time later to read the data.

it is being addressed, and the master responds with the 8-bit register address. The master then sends a stop or

restart condition, and may address another slave. Some time later the master sends a start or restart condition, and

register address location that had previously been set up.

I

Slave Address

Register Address

Slave Address B

Data

NACK

S

W A

A

S/Sr

R A

P

P

Slave Address A

S

S: Start Condition

Slave Address: 7 bit

W: Write = ‘0’

Register Address: 8 bit

R: Read = ‘1’

Data: 8 bit

A: Acknowledge (sent by slave)

NACK: Non-Acknowledge (sent by master)

Sr: Repeated Start Condition

P: Stop condition

Register Address Setup Access

Master Addresses

other Slaves

Register Read Access