Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 7/19/2024
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

5.8.6.5.7.3. Short Data Argument Data Structure

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 3 bytes.

Table 249.  Short Data Argument Data Structure
BIT-FIELD FIELD NAME WIDTH DESCRIPTION
31:23 DATA_BYTE_2 8

Data Byte -2

This field is used for storing the data byte -2.

23:16 DATA_BYTE_1 8

Data Byte -1

This field is used for storing the data byte -1.

15:8

DATA_BYTE_0/DB

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 only when both CP and DBP bits are enabled, otherwise the controller ignores this byte.

Note: When defining byte (DBP) is enabled in short data argument,
  • 1. The BYTE_STRB[0] bit is treated to be 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.
7:6 RESV 2 Reserved
5:3 BYTE_STRB 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

2:0 CMD_ATTR 3

Command Attribute

Defines the command type and its bit-field format.

  • 0: Transfer command
  • 1: Transfer argument
  • 2: Short data argument
  • 3: Address assignment command
  • 4-7: Reserved