AS7221 datasheet(20/36 Pages) AMSCO

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[v1-01] 2016-Dec-08

AS7221 − Detailed Description

I²C Write Access

Byte Write and Page Write formats are used to write data to the

slave.

Figure 23:

I²C Byte Write

Figure 24:

I²C Page Write

The transmission begins with the START condition, which is

generated by the master when the bus is in IDLE state (the bus

is free). The device-write address is followed by the word

address. After the word address any number of data bytes can

be sent to the slave. The word address is incremented internally,

in order to write subsequent data bytes on subsequent address

locations.

For reading data from the slave device, the master has to change

the transfer direction. This can be done either with a repeated

START condition followed by the device-read address, or simply

with a new transmission START followed by the device-read

address, when the bus is in IDLE state. The device-read address

is always followed by the 1st register byte transmitted from the

slave. In Read Mode any number of subsequent register bytes

can be read from the slave. The word address is incremented

internally.

Data

A P

Write WA++

Data 1

A P

Write WA++

……..

Data n

Write WA++

AS7221 Datasheet(PDF) 20 Page - ams AG