In I3C v1.1.1 the definition of the MLANE CCC in specification Section 5.1.9.3.30 and details of Multi-Lane Device configuration in Section 5.3.1.1 have been revised and re-written to improve clarity and resolve inconsistencies:

  • The MLANE CCC definition was unclear about how Group Addresses can be used with the CCC’s Direct SET form. It was also unclear whether all such ML-capable I3C Devices are required to support separate ML configurations for each assigned Group Address. This has now been clarified, and the full behavior of the MLANE CCC is now described in detail.
  • Multi-Lane configuration of I3C Devices that support multiple Addresses concurrently (i.e., Group Addresses and/or multiple Dynamic Addresses as Virtual Targets) has been clarified and expanded to cover possible cases of feature intersection. I3C v1.1.1 now describes how I3C Devices handle complex configurations, including the default configuration of newly-assigned Group Addresses based on the I3C Mode and the chosen Data Transfer Coding for Multi-Lane.
  • Figures in Section 5.3 showing sample ML Frame formats in HDR Modes included a spurious Repeated START, after the Enter HDR CCC and before Multi-Lane transfers begin in the HDR Mode. The v1.1.1 specification corrects these diagrams; they now conform to the Section 5.2.1.3 text.
  • In addition, the I3C WG discovered complexities regarding I3C Devices that support HDR-BT Mode and its Alternate Mode Data Transfer Codings (see specification Section 5.3.2.4.1) with multiple Addresses. These nuanced issues were discovered after I3C v1.1’s release and publication, and their full impact was only realized after deep review and investigation by implementers.
  • In the v1.1.1 specification, the definitions of HDR-BT ML Data Transfer Codings address additional inconsistencies and typographical errors.

All of these I3C v1.1.1 changes are intended to clarify Multi-Lane, in order to help resolve potential implementation issues and interoperability concerns that might have resulted in differing or incorrect interpretations, including potential assumptions that there are unstated (i.e., implicitly defined) requirements.

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I3C