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OBI is the specification repository for the OpenBus Interface, a lightweight on-chip protocol used by several CORE-V embedded processors for instruction and data-memory access. The repository publishes versioned specification documents rather than RTL, while processor manuals and verification projects provide concrete master, slave, and agent implementations. Use it when integrating a CORE-V memory interface or building compatible interconnect and verification components.
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Category: IP ComponentsStatus: Editorial · MatureBest for: Engineer
At a glance
- Integration boundary: select the OBI version implemented by the target core and peripheral; the newest specification does not automatically describe every existing core interface
- Artifact type: versioned protocol specification rather than RTL
- Published documents: OBI v1.0 through OBI v1.6.0 are present in the repository
- CORE-V usage: instruction and data-memory interfaces in processors including CV32E40P and CV32E20
- Implementation boundary: concrete protocol logic and verification agents live in consuming core and DV repositories
Further resources
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IP ComponentsDocumentation
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OpenHWRISC-VIPDocumentationBus InterfaceSpecificationOBI
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Engineer
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Data as of Oct 12, 2026
Verified adoption, contributor and lineage records, educational use, presentations, articles, and ecosystem data will be added incrementally from named sources.
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