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Avalon Packets to Transactions Converter Core

Transaction Packet Format

Byte	Field	Description
0	Transaction code	Type of transaction. See Properties of Avalon-ST Interfaces table.
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

Byte	Field	Description
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.

Supported Transactions

Transaction Code	Avalon-MM Transaction	Description
0x00	Write	non-incrementing address.	Writes data to the given address until the total number of bytes written to the same word address equals to the value specified in the size field.
0x04	Write	incrementing address.	Writes transaction data starting at the given address.
0x10	Read	non-incrementing address.	Reads 32 bits of data from the given address until the total number of bytes read from the same address equals to the value specified in the size field.
0x14	Read	incrementing address.	Reads the number of bytes specified in the size field starting from the given address.
0x7f	No transaction.	No transaction is initiated. You can use this transaction type for testing purposes. Although no transaction is initiated on the Avalon-MM interface	the core still returns a response packet for this transaction code.