Overview
ISO/IEC 24739-3:2010 (Information technology - AT Attachment with Packet Interface - Part 3: Serial transport protocols and physical interconnect, ATA/ATAPI‑7 V3) defines the serial interface between a host and storage device. The standard specifies connectors and cables, the electrical and logical characteristics of interconnect signals, and the protocols for transporting commands, data, and status over the serial interface. It covers the physical (PHY), link and transport layers that enable reliable, interoperable communication between host controllers and ATA/ATAPI storage devices.
Key topics and technical requirements
- Physical layer (PHY): connector specifications, cable assemblies, electrical specifications, common‑mode biasing, differential signalling, rise/fall times and test methods for bit/frame error rates.
- Connectors and mechanical requirements: drawings, pinouts, backplane and blind‑mating tolerances, connector locations and conformance rules.
- Link layer: encoding, primitives and framing (examples include ALIGN, CONT, DMAT, EOF, HOLD/HOLDA, PMREQ/PMACK, R_ERR, R_OK, SYNC, WTRM, X_RDY), CRC calculation, scrambling and repeated‑primitive suppression, and link state diagrams.
- Transport layer: Frame Information Structure (FIS) formats and FIS types (e.g., Register, Set Device Bits, DMA Activate, First Party DMA Setup, BIST Activate, PIO Setup, Data), FIS construction/decomposition, host and device transport state machines.
- Testing and diagnostics: BIST (built‑in self test), loopback tests, frame/bit error rate testing, test patterns and loopback requirements, SSC profile test methods.
- Elasticity buffer management: mechanisms for clock and data rate variation handling and data flow control.
Applications and who uses it
- Hardware designers: motherboard, host controller and storage device engineers use this standard to design compliant physical interfaces and PHY electronics.
- Connector and cable manufacturers: implement mechanical, electrical and conformance requirements for interconnect assemblies.
- Firmware and driver developers: implement transport layer logic, FIS handling and link state management for ATA/ATAPI‑7 serial devices.
- Test labs and QA teams: perform BER/FER testing, BIST/loopback verification and conformance validation.
- System integrators: ensure interoperability and reliable data transport between hosts and storage devices in servers, workstations and embedded systems.
Related standards
- Related ATA/ATAPI family and physical-interface standards (other parts of ISO/IEC 24739) and vendor specifications that reference ATA/ATAPI‑7 for serial transport and connector interoperability.
This standard is essential for ensuring interoperable, electrically robust serial storage interfaces and for implementing ATA/ATAPI‑7 compliant host–device systems.