Intel® Quartus® Prime Standard Edition User Guide: Platform Designer

ID 683364
Date 12/15/2018
Public
Document Table of Contents

4.8.2.1. Packets to Transactions Converter Data Packet Formats

A response packet is returned for every write transaction. The core also returns a response packet if a no transaction (0x7f) is received. An invalid transaction code is regarded as a no transaction. For read transactions, the core returns the data read.

The Packets to Transactions Converter core expects incoming data streams to be in the formats shown in the table below.

Table 153.  Data Packet Formats

Byte

Field

Description

Transaction Packet Format

0

Transaction code

Type of transaction.

1

Reserved

Reserved for future use.

[3:2]

Size

Transaction size in bytes. For write transactions, the size indicates the size of the data field. For read transactions, the size indicates the total number of bytes to read.

[7:4]

Address

32-bit address for the transaction.

[n:8]

Data

Transaction data; data to be written for write transactions.

Response Packet Format

0

Transaction code

The transaction code with the most significant bit inversed.

1

Reserved

Reserved for future use.

[4:2]

Size

Total number of bytes read/written successfully.