{
  "slug": "scsi-primary-commands",
  "term": "SCSI Primary Commands",
  "aliases": [
    "SPC"
  ],
  "definition": "SCSI Primary Commands defines a common device model and commands shared across SCSI device types.",
  "note": "SPC is used alongside a device-type command standard, rather than replacing it. [t10-families]\n\nShared applicability does not mean every listed command is mandatory. SPC-4 clause 1 distinguishes mandatory and optional commands and treats features as optional unless specified otherwise. Identify the applicable revision and device support before relying on a feature. [spc4-scope]\n\nREPORT SUPPORTED OPERATION CODES provides capability-discovery data; naming an opcode is not the same as probing a device. [sg-opcodes]",
  "citations": [
    {
      "id": "t10-families",
      "title": "T10 working drafts: SAM, SPC and device-type command families; descriptive index, not normative text",
      "url": "https://www.t10.org/drafts.htm",
      "accessed": "2026-11-10"
    },
    {
      "id": "spc4-scope",
      "title": "INCITS 513-2015 (R2020), SPC-4 public preview: introduction p. xli and clause 1 p. 1",
      "url": "https://webstore.ansi.org/preview-pages/INCITS/preview_INCITS%2B513-2015%2B(R2020).pdf",
      "accessed": "2026-11-10"
    },
    {
      "id": "sg-opcodes",
      "title": "Doug Gilbert, sg_opcodes(8), source at 8799caa3741b2b1640970747aeb84f17dbbaad86: description, --opcode, --enumerate and --rctd",
      "url": "https://raw.githubusercontent.com/doug-gilbert/sg3_utils/8799caa3741b2b1640970747aeb84f17dbbaad86/doc/sg_opcodes.8",
      "accessed": "2026-11-10"
    },
    {
      "id": "hesela-scsi",
      "title": "Hesela: SCSI command, logical-unit and transport boundaries",
      "url": "https://hesela.com/tech/scsi/",
      "accessed": "2026-11-10"
    }
  ],
  "status": "unknown",
  "advantages": [],
  "limitations": [],
  "related": [
    "scsi",
    "t10-scsi",
    "scsi-architecture-model",
    "scsi-block-commands",
    "scsi-report-supported-operation-codes"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-11-10",
  "provenance": [
    "Foundational standards-family definition; public descriptive sources and the SPC-4 preview reviewed, not full restricted standards or device conformance."
  ]
}