4.5. PFT packet formats

Table 4.1 lists the PFT packet formats.

Table 4.1. Packet formats

Header:PayloadCategory [a]Remarks
DescriptionValue
A-syncb0000 0000At least 5 bytesSync.

Alignment synchronization, see A-sync, alignment synchronization packet.

I-syncb0000 10005-14 bytesSync.

Instruction flow synchronization, see I-sync, instruction synchronization packet.

Atomb1xxx xxx00-4 bytesInstructionSee Atom packet.
Branch addressbCxxx xxx10-11 [b] bytesInstruction

C is 1 if another byte follows, and 0 otherwise.

See Branch address packet.

Waypoint updateb0111 00101-5 bytesInstructionSee Waypoint update packet.
Triggerb0000 1100NoneMisc.See Trigger packet.
Context IDb0110 11101-4 bytesInstruction

See Context ID packet.

VMIDb001111001 byteInstructionSee VMID packets
Timestamp [c]b0100 0x101-14 bytesSync.See Timestamp packet.
Exception returnb0111 0110NoneInstructionSee Exception return packet.
Ignoreb0110 0110NoneMisc.See Ignore packet.

[a] Sync. = Synchronization, Misc. = Miscellaneous.

[b] The header byte forms part of the address section of the branch address packet.

[c] The timestamp header is also referred to as a T-sync header. See Timestamp synchronization.


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