Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families 75
Datasheet Volume One
2.5.5 Client Responses

2.5.5.1 Abort FCS

The Client responds with an Abort FCS under the following conditions:
• The decoded command is not understood or not supported on this processor (this
includes good command codes with bad Read Length or Write Length bytes).
• Assured Write FCS (AW FCS) failure. Under most circumstances, an Assured Write
failure will appear as a bad FCS. However, when an originator issues a poorly
formatted command with a miscalculated AW FCS, the client will intentionally abort
the FCS in order to guarantee originator notification.

2.5.5.2 Completion Codes

Some PECI commands respond with a completion code byte. These codes are designed
to communicate the pass/fail status of the command and may also provide more
detailed information regarding the class of pass or fail. For all commands listed in
Section 2.5.2 that support completion codes, the definition in the following table
applies. Throughout this document, a completion code reference may be abbreviated
with ‘CC’.
An originator that is decoding these commands can apply a simple mask as shown in
Tabl e 2-21 to determine a pass or fail. Bit 7 is always set on a command that did not
complete successfully and is cleared on a passing command.
Note: The codes explicitly defined in Tabl e 2-22 may be useful in PECI originator response
algorithms. Reserved or undefined codes may also be generated by a PECI client
device, and the originating agent must be capable of tolerating any code. The Pass/Fail
mask defined in Tabl e 2-21 applies to all codes, and general response policies may be
based on this information. Refer to Section2.5.6 for originator response policies and
recommendations.
Table 2-21. Completion Code Pass/Fail Mask
0xxx xxxxb Command passed
1xxx xxxxb Command failed
Table 2-22. Device Specific Completion Code (CC) Definition
Completion
Code Description
0x40 Command Passed
CC: 0x80 Response timeout. The processor was not able to generate the required response in a timely
fashion. Retry is appropriate.
CC: 0x81 Response timeout. The processor was not able to allocate resources for servicing this
command. Retry is appropriate.
CC: 0x82 The processor hardware resources required to service this command are in a low power
state. Retry may be appropriate after modification of PECI wake mode behavior if
appropriate.
CC: 0x83-8F Reserved
CC: 0x90 Unknown/Invalid/Illegal Request
CC: 0x91 PECI control hardware, firmware or associated logic error. The processor is unable to process
the request.
CC: 0x92-9F Reserved