This section presents requirements for ATA hardware that is compatible with Windows NT, including adapters, peripherals, and any device that uses an ATA controller.
| Windows NT Server | Enterprise Edition | Small Business Server | |
| Basic Server: | Recommended | Required | Recommended |
| Enterprise: | Recommended | Required | Recommended |
| SOHO: | Recommended | Required | Recommended |
ATA disks should not be present in a server, and ISA-based ATA is not allowed for servers. If ATA is implemented in a system, the ATA host controller and peripheral must meet all related requirements for devices and drivers, and they must meet the requirements defined in this section.
A server running Windows NT Server/Enterprise Edition can use an ATA device only as a boot or installation device.
Required
All ATA controllers and peripherals must meet the hardware and software design requirements listed in the current version of the ATA/ATAPI-4 Revision 17 standard or later.
Required
PCI dual ATA adapters must be designed so that either channel can be used at any time; the operating system must not have to serialize access between the primary and secondary channel. Therefore, either the two channels are totally independent or a hardware arbitrator protects anything shared, such as a PIO read pre-fetch buffer.
A design implementing a single FIFO with a hardware solution to synchronize access to both channels meets this requirement if the design does not require that a request on one channel be completed before another can be started. A software-based solution is not acceptable.
ATA-based systems must be tested with ATA DMA enabled; the system must not have an embedded single-FIFO dual-channel ATA controller.
Section 5.0 of the Compaq, Intel, Phoenix BIOS Boot Specification defines the implementation for dual asynchronous channels.
Dual-channel controllers that require special software to serialize channel I/O for a single prefetch FIFO do not meet these requirements. Such designs require serial access to one of four devices, defeating the primary advantage of asynchronous dual-channel controllers. Furthermore, such devices are non-standard and require custom driver support.
Required
To enable support for ATA disk drives have capacities greater than 528 MB, the system BIOS must use LBA— the LBA bit in the Device/Head register must be set to one— for all read and write operations to the device. The ATA 1226 technical report defines the proper implementation of LBA.
Although ATAPI was defined to be transparent to the BIOS, the BIOS must recognize the presence of ATAPI devices using the signature defined in SFF 8020i.
Recommended
The system BIOS or option ROM should provide boot support for ATAPI bootable floppy disk drive in compliance with ATAPI Removable Media BIOS Specification (ARMD), Version 1.0 or later. Complying with this specification provides Int13h and Int40h support for bootable floppy drives as the primary or secondary floppy device.
Required
All controllers and ATA peripherals must support Ultra DMA (also known as Ultra-ATA) at transfer rates up to 33 MB per second as defined in ATA/ATAPI-4 Revision 17. In addition to improved transfer rates, Ultra DMA also provides error checking for improved robustness over previous ATA implementations. PCI chip sets must implement DMA as defined in SFF 8038i.
ATA drives must comply with ATA-4, which defines the programming register set for PCI ATA bus master DMA, to ensure fully featured hardware and Windows-compatible device driver support.
Recommended support includes:
An exemption exists for ISA-based, ATA-connected CD drives used solely for the purpose of software installation on a server system. Such devices cannot be used for any other purpose, including access to data by client systems.
Required
Pin 1 orientation must be designated by one edge of the ribbon cable and also on the keyed connector of the ATA or ATAPI controller and peripheral device. Designation of the keyed connector must be clearly indicated on or near the connector.
Required
This standard defines standard hardware and software design guidelines for ATAPI devices. See also requirement #126, “System and Option ROMs support Int 13h Extensions.”
Required
This standard defines the enumeration process for all ATAPI devices.
Required
ATAPI devices must respond to the DEVICE RESET command regardless of their internal state, as defined in the ATA/ATAPI-4 standard. The controller can be reset by going into a power-on state (requests cleared, signature present), but any non-default mode values must be left in their current state with the DRV bit unchanged.
Devices that do not implement the PACKET command feature set, such as hard disk drives, must not implement the DEVICE RESET command.
Required
To avoid having two devices in the system claim 3F7h and 377h, these addresses must not be claimed for device registers by ATA devices.
It is recognized that some FDC devices claim this range. Such devices can be implemented in a server system; however, the system manufacturer must ensure that only a single device in the system claims this range.
Required
The ATA drive must implement the ATA STANDBY command according to the ATA standard. This command is defined in ATA/ATAPI-4.
The hard disk drive should spin up and be able to complete a Read operation within 10 seconds of applying power or leaving ATA STANDBY mode and transitioning to ATA ACTIVE, as specified in the Storage Device Class Power Management Reference Specification, Version 1.0 or later.