TPS65982: Byte Order for 32 bit I2C Reads

Steve Riley

Part Number: TPS65982

Tool/software:

When I2C is used to read a 32 bit register, what is the bit order (of the 32 bits) sent over the 4 bytes of the Read?
Does the first byte read (via I2C) contain bits 32..24 or 7..0?

11 months ago

0 Conner Gillette 11 months ago

TI__Genius 13880 points

Hi Steve,

MSb to LSb goes from left to right in the below diagram:

Kind regards,

Conner

0 Steve Riley 11 months ago

Intellectual 385 points

The info you provided is for the data within a Byte. When reading a 32 bit or more register, is the first byte sent the least significant 8 bits of the large word? For example, if a 32 bit register is read, 4 I2C bytes are read, Is the data packed like:

Byte 1 (first byte on I2C read) = [7:0]
Byte 2 = [15..8]

Byte 3 = [23..16]

Byte 4 (last byte on I2C read) = [31..24]

0 Conner Gillette 11 months ago in reply to Steve Riley

TI__Genius 13880 points

Yes, that matches the datasheet.

Regards,

Conner

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TPS65982: Byte Order for 32 bit I2C Reads