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ECR & ECN Overview

The PCI-SIG has been a successful computing standard organization due to industry-wide participation. PCI-SIG Members have the right to review, comment and request changes on all specifications. This review process begins with an Engineering Change Request (ECR) and may ultimately result in an Engineering Change Notice (ECN) to the specification. This ECR/ECN process allows PCI-SIG to achieve industry-wide buy-in, awareness and most importantly, full compliance with new changes that will affect millions of platforms and tens of millions of add-in devices.

How to Submit an ECR

  1. Download and fill-out a PCI-SIG Engineering Change Request (ECR) form (103k Doc).
  2. Upload the completed ECR form using the online ECR Tracking Application.

How an ECR Becomes Part of a PCI-SIG Specification

Review the complete process of how an ECR becomes an ECN.

At any one time, there can be only one current version of all PCI specifications and design guides, termed the “production version.”  At the same time, there may also be proposed revisions to the specifications and design guides that are not yet approved and are held confidential (as deemed necessary by the Board of Directors) within the PCI-SIG Workgroups.

All PCI-SIG Members may submit requests (ECRs) to revise the PCI specifications and design guides.  ECRs may be rejected or may result in an Engineering Change Notification (ECN).  ECNs are the official means of changing PCI-SIG Specifications and related documentation.

Request to Allocate Reserved Resource  

“Reserved resources” are anything designated as “reserved” in a PCI specification, including: connector pins, command encodings, bit fields, etc. Allocation of reserved resources will be considered if the function is deemed to be important for the continued growth and long-term well being of PCI, and there is no other effective way for the function to be implemented except using a reserved resource.  Please provide detailed supporting discussion as well as an examination of possible alternatives in question 4 of the ECR form.  Issues to be addressed include:

  1. Backward compatibility: Describe how devices, cards, systems, etc. with the new function would interoperate with devices, cards, devices, systems, etc. without the new function.  For example, how would an add-in card with a new pin assignment work with a system designed before the new pin assignment? Conversely, how would an add-in card designed before the new pin assignment work with a system designed after the new pin assignment?

  2. Limitations of other alternates: Explain why the desired function cannot be performed without assigning reserved resources, or why such alternatives have disadvantages that make them less desirable than assigning reserved resources.

Resubmission and Appeal

The originator of a request that was not approved can redraft the original request.  A rewritten proposal will be treated as a new proposal and will be evaluated using the procedures described above. The originator of a request that was not approved can also submit an appeal to the Board of Directors.  The appeal must be made electronically and addressed to the Secretary.

Please send an email to PCI-SIG Administration with any inquiries to this process.