Short Data Argument Data Structure

The Short Data Argument Data Structure is used to provide payload-related information for the TX transfers when the payload size is less than or equal to three bytes.

Note: Short Data Argument is not supported for HDR transfers because, in HDR modes, a maximum of two words can be transferred in this format.
Table 24-5. Short Data Argument Data Structure
SL.NoField Name

Bit Field

WidthDescription

1

CMD_ATTR

2:0

3

Command Attribute

Defines the command type and its bit field format.
  • 4-7: Reserved
  • 3: Address Assignment Command
  • 2: Short Data Argument
  • 1: Transfer Argument
  • 0: Transfer Command

2

BYTE_STRB

5:3

3

Byte Strobe

This field is used to select the valid data bytes of the Short Data Argument.
  • BYTE_STRB[0] - Data Byte -0 Valid Qualifier
  • BYTE_STRB[1] - Data Byte -1 Valid Qualifier
  • BYTE_STRB[2] - Data Byte -2 Valid Qualifier
  • Valid combinations = 3'b001, 3'b011 and 3'b111

3

RESV

7:6

2

Reserved

4

DATA_BYTE _0/DB

15:8

8

Data Byte -0/Defining Byte: This field is used for storing the Data Byte -0. DB indicates the 8-bit Defining Byte to be transferred in the CCC transfer. This byte is valid as a Defining Byte (DB) when both CP and DBP bits are enabled; otherwise, it's used as DATA_BYTE_0.

Note: When the Defining Byte (DBP) is enabled in Short Data Argument: 1. The BYTE_STRB[0] bit is treated as always enabled, whether or not you set it. 2. The maximum possible payload bytes to be sent is ‘2’ due to the first byte being occupied by the Defining Byte.

5

DATA_BYTE_1

23:16

8

Data Byte -1: This field is used for storing Data Byte -1.

6

DATA_BYTE_2

31:23

8

Data Byte -2: This field is used for storing Data Byte -2.