Data Sheet

Page 24 ams Datasheet

Document Feedback [v1-04] 2018-Jul-09

AS7265x − Detailed Description

Figure 24:

I²C Slave Device Address and Physical Registers

I²C Virtual Register Write Access

I²C Virtual Resister Byte Write, detailed below, shows the

pseudocode necessary to write virtual registers on the

AS72651. Note that, because the actual registers of interest are

realized as virtual registers, a means of indicating whether there

is a pending read or write operation of a given virtual register

is needed. To convey this information, the most significant bit

of the virtual register address is used as a marker. If it is 1, then

a write is pending, otherwise the slave is expecting a virtual

read operation. The pseudocode illustrates the proper tech-

nique for polling of the I²C slave status register to ensure the

slave is ready for each transaction.

Entity Description Note

Device Slave Address 8-bit slave address

Byte = 1001001x (device address = 49 hex)

• x= 1 for Master Read (byte = 93 hex)

• x= 0 for Master Write (byte = 92 hex)

STATUS Register

I²C slave interface STATUS

Bit 1: TX_VALID

• 0 - New data may be written to WRITE register

• 1 -WRITE register occupied. Do NOT write.

Bit 0: RX_VALID

• 0 -No data is ready to be read in READ register.

• 1 -Data byte available in READ register.

WRITE Register

I²C slave interface WRITE

• 8-Bits of data written by the I²C Master

intended for receipt by the I²C slave. Used for

both virtual register addresses and write data.

READ Register

I²C slave interface

READ register. Read-only.

• 8-Bits of data to be read by the I²C Master.