SATA

SATA (Serial AT Attachment) is a computer bus interface announced in 2000 that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Revision 1.0 of the specification was released in January 2003¹. Serial ATA succeeded the earlier Parallel ATA (PATA) standard to become the predominant interface for storage devices. Its advantages over the earlier PATA interface include reduced cable size and cost (seven conductors instead of 40 or 80), native hot swapping, faster data transfer through higher signaling rates, and more efficient transfer through an (optional) I/O queuing protocol. Serial ATA industry compatibility specifications originate from the Serial ATA International Organization (SATA-IO) which are then released by the INCITS Technical Committee T13, AT Attachment (INCITS T13).

SATA (Serial AT Attachment) is a computer bus interface announced in 2000 that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Revision 1.0 of the specification was released in January 2003. Serial ATA succeeded the earlier Parallel ATA (PATA) standard to become the predominant interface for storage devices. Its advantages over the earlier PATA interface include reduced cable size and cost (seven conductors instead of 40 or 80), native hot swapping, faster data transfer through higher signaling rates, and more efficient transfer through an (optional) I/O queuing protocol. Serial ATA industry compatibility specifications originate from the Serial ATA International Organization (SATA-IO) which are then released by the INCITS Technical Committee T13, AT Attachment (INCITS T13).

SATA revision 1.0 (1.5 Gbit/s, 150 MB/s, Serial ATA-150)

Revision 1.0a was released on January 7, 2003. First-generation SATA interfaces, now known as SATA 1.5 Gbit/s, communicate at a rate of 1.5 Gbit/s, and do not support Native Command Queuing (NCQ). Taking 8b/10b encoding overhead into account, they have an actual uncoded transfer rate of 1.2 Gbit/s (150 MB/s). The theoretical burst throughput of SATA 1.5 Gbit/s is similar to that of PATA/133, but newer SATA devices offer enhancements such as NCQ, which improve performance in a multitasking environment. During the initial period after SATA 1.5 Gbit/s finalization, adapter and drive manufacturers used a "bridge chip" to convert existing PATA designs for use with the SATA interface. Bridged drives have a SATA connector, may include either or both kinds of power connectors, and, in general, perform identically to their native-SATA equivalents. , the fastest 10,000 rpm SATA hard disk drives could transfer data at maximum (not average) rates of up to 157 MB/s, which is beyond the capabilities of the older PATA/133 specification and also exceeds the capabilities of SATA 1.5 Gbit/s.

SATA revision 2.0 (3 Gbit/s, 300 MB/s, Serial ATA-300)

SATA revision 2.0 was released in April 2004¹, introducing Native Command Queuing (NCQ). It is backward compatible with SATA 1.5 Gbit/s. Second-generation SATA interfaces run with a native transfer rate of 3.0 Gbit/s that, when accounted for the 8b/10b encoding scheme, equals to the maximum uncoded transfer rate of 2.4 Gbit/s (300 MB/s). The theoretical burst throughput of the SATA revision 2.0, which is also known as the SATA 3 Gbit/s, doubles the throughput of SATA revision 1.0. All SATA data cables meeting the SATA spec are rated for 3.0 Gbit/s and handle modern mechanical drives without any loss of sustained and burst data transfer performance. However, high-performance flash-based drives can exceed the SATA 3 Gbit/s transfer rate; this is addressed with the SATA 6 Gbit/s interoperability standard.

SATA revision 2.5

Announced in August 2005, SATA revision 2.5 consolidated the specification to a single document.

SATA revision 2.6

Announced in February 2007, SATA revision 2.6 introduced the following features: Slimline connector Micro connector (initially for 1.8” HDD) Mini Internal Multilane cable and connector Mini External Multilane cable and connector NCQ Priority NCQ Unload Enhancements to the BIST Activate FIS Enhancements for robust reception of the Signature FIS

SATA revision 3.0 (6 Gbit/s, 600 MB/s, Serial ATA-600)

Serial ATA International Organization (SATA-IO) presented the draft specification of SATA 6 Gbit/s physical layer in July 2008, and ratified its physical layer specification on August 18, 2008. The full 3.0 standard was released on May 27, 2009. Third-generation SATA interfaces run with a native transfer rate of 6.0 Gbit/s; taking 8b/10b encoding into account, the maximum uncoded transfer rate is 4.8 Gbit/s (600 MB/s). The theoretical burst throughput of SATA 6.0 Gbit/s is double that of SATA revision 2.0. It is backward compatible with earlier SATA implementations. The SATA 3.0 specification contains the following changes: 6 Gbit/s for scalable performance. Continued compatibility with SAS, including SAS 6 Gbit/s, as per "a SAS domain may support attachment to and control of unmodified SATA devices connected directly into the SAS domain using the Serial ATA Tunneled Protocol (STP)" from the SATA Revision 3.0 Gold specification. Isochronous Native Command Queuing (NCQ) streaming command to enable isochronous quality of service data transfers for streaming digital content applications. An NCQ management feature that helps optimize performance by enabling host processing and management of outstanding NCQ commands. Improved power management capabilities. A small low insertion force (LIF) connector for more compact 1.8-inch storage devices. A 7 mm optical disk drive profile for the slimline SATA connector (in addition to the existing 12.7 mm and 9.5 mm profiles). Alignment with the INCITS ATA8-ACS standard. In general, the enhancements are aimed at improving quality of service for video streaming and high-priority interrupts. In addition, the standard continues to support distances up to one meter. The newer speeds may require higher power consumption for supporting chips, though improved process technologies and power management techniques may mitigate this. The later specification can use existing SATA cables and connectors, though it was reported in 2008 that some OEMs were expected to upgrade host connectors for the higher speeds.

SATA revision 3.1

Released in July 2011¹, SATA revision 3.1 introduced or changed the following features: mSATA, for solid-state drives in mobile computing devices, a PCI Express Mini Card-like connector that is electrically SATA. The connector was also used in some desktop computers, such as certain HP business PCs. Zero-power optical disk drive, a SATA optical drive that draws no power when idle. Queued TRIM Command, improves solid-state drive performance. Required Link Power Management, reduces overall system power demand of several SATA devices. Hardware Control Features, enable host identification of device capabilities. Universal Storage Module (USM), a new standard for cableless plug-in (slot) powered storage for consumer electronics devices.

SATA revision 3.2

Released in August 2013¹, SATA revision 3.2 introduced the following features: The SATA Express specification defines an interface that combines both SATA and PCI Express buses, making it possible for both types of storage devices to coexist. By employing PCI Express, a much higher theoretical throughput of 1969 MB/s is possible. The SATA M.2 standard is a small form factor implementation of the SATA Express interface, with the addition of an internal USB 3.0 port; see the M.2 (NGFF) section below for a more detailed summary. microSSD introduces a ball grid array electrical interface for miniaturized, embedded SATA storage. USM Slim reduces thickness of Universal Storage Module (USM) from to . DevSleep enables lower power consumption for always-on devices while they are in low-power modes such as InstantGo (which used to be known as Connected Standby). Hybrid Information provides higher performance for solid-state hybrid drives.

SATA revision 3.3

Released in February 2016¹, SATA revision 3.3 introduced the following features: Shingled magnetic recording (SMR) host-control support (device-controlled SMR HDDs are the same as standard CMR HDDs with respect to SATA compatibility). SMR provides a 25 percent or greater increase in hard disk drive capacity by overlapping tracks on the media. Optional Zoned ATA Command Set (ZAC) feature. Power Disable feature (see PWDIS pin) allows for remote power cycling of SATA drives and a Rebuild Assist function that speeds up the rebuild process to help ease maintenance in the data center. Transmitter Emphasis Specification increases interoperability and reliability between host and devices in electrically demanding environments. An activity indicator and staggered spin-up can be controlled by the same pin, adding flexibility and providing users with more choices. The new Power Disable feature (similar to the SAS Power Disable feature) uses Pin 3 of the SATA power connector. Some legacy power supplies that provide 3.3 V power on Pin 3 would force drives with Power Disable feature to get stuck in a hard reset condition preventing them from spinning up. The problem can usually be eliminated by using a simple “Molex to SATA” power adaptor to supply power to these drives.

SATA revision 3.4

Released in June 2018¹, SATA revision 3.4 introduced the following features that enable monitoring of device conditions and execution of housekeeping tasks, both with minimal impact on performance: Durable/Ordered Write Notification: enables writing selected critical cache data to the media, minimizing impact on normal operations. Device Temperature Monitoring: allows for active monitoring of SATA device temperature and other conditions without impacting normal operation by utilizing the SFF-8609 standard for out-of-band (OOB) communications. Device Sleep Signal Timing: provides additional definition to enhance compatibility between manufacturers’ implementations.

SATA revision 3.5

Released in July 2020¹, SATA revision 3.5 introduces features that enable increased performance benefits and promote greater integration of SATA devices and products with other industry I/O standards: Device Transmit Emphasis for Gen 3 PHY: aligns SATA with other characteristics of other I/O measurement solutions to help SATA-IO members with testing and integration. Defined Ordered NCQ Commands: allows the host to specify the processing relationships among queued commands and sets the order in which commands are processed in the queue. Command Duration Limit Features: reduces latency by allowing the host to define quality of service categories, giving the host more granularity in controlling command properties. The feature helps align SATA with the "Fast Fail" requirements established by the Open Compute Project (OCP) and specified in the INCITS T13 Technical Committee standard. SATA revision 3.5a was released in March 2021¹.

Cables, connectors, and ports

Connectors and cables present the most visible differences between SATA and parallel ATA drives. Unlike PATA, the same connectors are used on 3.5-inch SATA hard disks (for desktop and server computers) and 2.5-inch disks (for portable or small computers). Standard SATA connectors for both data and power have a conductor pitch of . Low insertion force is required to mate a SATA connector. A smaller mini-SATA or mSATA connector is used by smaller devices such as 1.8-inch SATA drives, some DVD and Blu-ray drives, and mini SSDs. A special eSATA connector is specified for external devices, and an optionally implemented provision for clips to hold internal connectors firmly in place. SATA drives may be plugged into SAS controllers and communicate on the same physical cable as native SAS disks, but SATA controllers cannot handle SAS disks. Female SATA ports (on motherboards for example) are for use with SATA data cables that have locks or clips to prevent accidental unplugging. Some SATA cables have right- or left-angled connectors to ease connection to circuit boards.

Data connector

The SATA standard defines a data cable with seven conductors (three grounds and four active data lines in two pairs) and 8 mm wide wafer connectors on each end. SATA cables can have lengths up to , and connect one motherboard socket to one hard drive. PATA ribbon cables, in comparison, connect one motherboard socket to one or two hard drives, carry either 40 or 80 wires, and are limited to in length by the PATA specification; however, cables up to are readily available. Thus, SATA connectors and cables are easier to fit in closed spaces and reduce obstructions to air cooling. Some cables even include a locking feature, whereby a small (usually metal) spring holds the plug in the socket. SATA connectors may be straight, upward-angled, downward-angled, leftward-angled, or rightward-angled. Angled connectors allow lower-profile connections. Downward-angled connectors lead the cable immediately away from the drive, on the circuit-board side. Upward-angled connectors lead the cable across the drive towards its top. One of the problems associated with the transmission of data at high speed over electrical connections is described as noise, which is due to electrical coupling between data circuits and other circuits. As a result, the data circuits can both affect other circuits and be affected by them. Designers use a number of techniques to reduce the undesirable effects of such unintentional coupling. One such technique used in SATA links is differential signaling. This is an enhancement over PATA, which uses single-ended signaling. The use of fully shielded, dual coax conductors, with multiple ground connections, for each differential pair improves isolation between the channels and reduces the chances of lost data in difficult electrical environments. There are SATADOM variants of the connector merging power supply into the 7-pin connector, saving space in industrial setups. The "pin 7" variation repurposes pin 7 for +5V power. The "pin 8" variation repurposes two unnumbered shielding pins for power GND and +5V.

Additional pins

Some SATA drives, in particular mechanical ones, come with an extra 4 or more jumper pin interface which isn't uniformly standardized but nevertheless serves similar purpose defined by each drive manufacturer. As IDE drives used those extra pins for setting up Master and Slave drives, on SATA drives, those pins are generally used to select different Power modes for use in USB-SATA bridges or enables additional features like Spread Spectrum Clocking, SATA Speed Limit or Factory Mode for Diagnostics and Recovery, by the use of a jumper.

eSATAp

port eSATAp stands for powered eSATA. It is also known as Power over eSATA, Power eSATA, eSATA/USB Combo, or eSATA USB Hybrid Port (EUHP). An eSATAp port combines the four pins of the USB 2.0 (or earlier) port, the seven pins of the eSATA port, and optionally two 12 V power pins. Both SATA traffic and device power are integrated in a single cable, as is the case with USB but not eSATA. The 5 V power is provided through two USB pins, while the 12 V power may optionally be provided. Typically desktop, but not notebook, computers provide 12 V power, so can power devices requiring this voltage, typically 3.5-inch disk and CD/DVD drives, in addition to 5 V devices such as 2.5-inch drives. Both USB and eSATA devices can be used with an eSATAp port, when plugged in with a USB or eSATA cable, respectively. An eSATA device cannot be powered via an eSATAp cable, but a special cable can make both SATA or eSATA and power connectors available from an eSATAp port. An eSATAp connector can be built into a computer with internal SATA and USB, by fitting a bracket with connections for internal SATA, USB, and power connectors and an externally accessible eSATAp port. Though eSATAp connectors have been built into several devices, manufacturers do not refer to an official standard.

Mini-SATA (mSATA)

Mini-SATA (abbreviated as mSATA), which is distinct from the micro connector, was announced by the Serial ATA International Organization on September 21, 2009. Applications include netbooks, laptops and other devices that require a solid-state drive in a small footprint. The physical dimensions of the mSATA connector are identical to those of the PCI Express Mini Card interface, but the interfaces are electrically incompatible; the data signals (TX±/RX± SATA, PETn0 PETp0 PERn0 PERp0 PCI Express) need a connection to the SATA host controller instead of the PCI Express host controller. The M.2 specification has superseded both mSATA and PCI Express Mini.

SFF-8784 connector

Slim 2.5-inch SATA devices, in height, use the twenty-pin SFF-8784 edge connector to save space. By combining the data signals and power lines into a slim connector that effectively enables direct connection to the device's printed circuit board (PCB) without additional space-consuming connectors, SFF-8784 allows further internal layout compaction for portable devices such as ultrabooks. Pins 1 to 10 are on the connector's bottom side, while pins 11 to 20 are on the top side.

SATA Express

; to the right of them are common SATA connectors (dark gray). SATA Express, initially standardized in the SATA 3.2 specification, is an interface that supports either SATA or PCI Express storage devices. The host connector is backward compatible with the standard 3.5-inch SATA data connector, allowing up to two legacy SATA devices to connect. At the same time, the host connector provides up to two PCI Express 3.0 lanes as a pure PCI Express connection to the storage device, allowing bandwidths of up to 2 GB/s. Instead of the otherwise usual approach of doubling the native speed of the SATA interface, PCI Express was selected for achieving data transfer speeds greater than 6 Gbit/s. It was concluded that doubling the native SATA speed would take too much time, too many changes would be required to the SATA standard, and would result in a much greater power consumption when compared to the existing PCI Express bus. In addition to supporting legacy Advanced Host Controller Interface (AHCI), SATA Express also makes it possible for NVM Express (NVMe) to be used as the logical device interface for connected PCI Express storage devices. As M.2 form factor, described below, achieved much larger popularity, SATA Express is considered as a failed standard and dedicated ports quickly disappeared from motherboards.

M.2 (NGFF)

(2242) solid-state-drive (SSD) connected into USB 3.0 adapter and connected to computer M.2, formerly known as the Next Generation Form Factor (NGFF), is a specification for computer expansion cards and associated connectors. It replaces the mSATA standard, which uses the PCI Express Mini Card physical layout. Having a smaller and more flexible physical specification, together with more advanced features, the M.2 is more suitable for solid-state storage applications in general, especially when used in small devices such as ultrabooks or tablets. A M.2 SSD is "keyed" to prevent insertion of a card connector (male) to an incompatible socket (female) on the host. Typically, M.2 SSDs with a B key or B+M key are SATA, while M.2 SSDs with M key only are mostly NVMe only and incompatible with SATA. The M.2 standard is designed as a revision and improvement to the mSATA standard, so that larger printed circuit boards (PCBs) can be manufactured. While mSATA took advantage of the existing PCI Express Mini Card form factor and connector, M.2 has been designed to maximize usage of the card space, while minimizing the footprint. Supported host controller interfaces and internally provided ports are a superset to those defined by the SATA Express interface. Essentially, the M.2 standard is a small form factor implementation of the SATA Express interface, with the addition of an internal USB 3.0 port.

U.2 (SFF-8639)

U.2, formerly known as SFF-8639. Like M.2, it carries a PCI Express electrical signal, however U.2 uses a PCIe 3.0 ×4 link providing a higher bandwidth of 32 Gbit/s in each direction. In order to provide maximum backward compatibility the U.2 connector also supports SATA and multi-path SAS.

SATA 1.5 Gbit/s and SATA 3 Gbit/s

The designers of SATA standard as an overall goal aimed for backward and forward compatibility with future revisions of the SATA standard. To prevent interoperability problems that could occur when next generation SATA drives are installed on motherboards with standard legacy SATA 1.5 Gbit/s host controllers, many manufacturers have made it easy to switch those newer drives to the previous standard's mode. Examples of such provisions include: Seagate/Maxtor has added a user-accessible jumper-switch, known as the "force 150", to enable the drive switch between forced 1.5 Gbit/s and 1.5/3 Gbit/s negotiated operation. Western Digital uses a jumper setting called OPT1 enabled to force 1.5 Gbit/s data transfer speed (OPT1 is enabled by putting the jumper on pins 5 and 6). Samsung drives can be forced to 1.5 Gbit/s mode using software that may be downloaded from the manufacturer's website. Configuring some Samsung drives in this manner requires the temporary use of a SATA-2 (SATA 3.0 Gbit/s) controller while programming the drive. The "force 150" switch (or equivalent) is also useful for attaching SATA 3 Gbit/s hard drives to SATA controllers on PCI cards, since many of these controllers (such as the Silicon Image chips) run at 3 Gbit/s, even though the PCI bus cannot reach 1.5 Gbit/s speeds. This can cause data corruption in operating systems that do not specifically test for this condition and limit the disk transfer speed.

Text derived from https://en.wikipedia.org/w/index.php?oldid=1374111267 under CC BY-SA 4.0; modifications have been made.