Viewing Decoded Payload For Ahci Commands - Keysight Technologies U4301 User Manual

10 Computing and Viewing Decoded Transactions
In the above example, the following transactions are a part of the ATA Command Write FPDMA
Queued super transaction.
1
2
3
4
5
6
For more information on visualize transaction, refer to
Transaction)"

Viewing Decoded Payload for AHCI Commands

For AHCI ATA IDENTIFY DEVICE and IDENTIFY (PACKET) DEVICE commands that retrieve
information in a specific data structure format, you can view the returned data structure in the same
format as defined in the Serial ATA specifications. The Transaction Decode tab displays the decoded
payload (all 256 words) for these commands to present their data structure as per the defined
format.
152
The first transaction is a memory write to the PxCI (Port x Command Issue) register to indicate
that a command has been built in memory for a command slot.
The second transaction is a memory read for the added command list entry.
The third transaction is a memory read of the Write FPDMA Queued command from the
command table.
The fourth transactions is a DMA Setup FIS (DSFIS) memory write to transfer data for the Write
FPDMA Queued command in the appropriate slot.
The fifth transaction is a PRD Table read transaction. This transaction further expands to display
the PRDT entry used for reading the transferred data.
The last transaction in the set is a memory write for updating the Set Device Bits FIS. This
indicates the completion of the Write FPDMA Queued command.
on page 133.
"Visualizing a Transaction Set (Super
Keysight U4301 PCIe Gen3 Analyzer User's Guide