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ISA Bus Current Use

PCI Slot Computer



NEW Computers with ISA Bus


WE SELL COMPUTERS WITH ISA Slot / ISA Bus. Change is inevitable. Why grumble about losing your ISA bus compatibility when you update your computers?

Preserve the usefulness of your data written and stored in older formats with Intel servers in tower or rackmount enclosures. Your business needs to stay flexible in the face of changing industry standards. Let NIXSYS configure the hardware you need.

Using our PC with ISA Bus can make a temporary task safe and secure. That way you won't have to rush or take the focus off of other business matters. The features we offer give you enough muscle to keep working without spending a fortune on transitional technology. It's all backed up by 2-year warranty.


ISA Bus Current Use

ISA bus is still used today for specialized industrial purposes. In 2008 IEI Technologies released a modern motherboard for Intel Core 2 Duo processors which, in addition to other special I/O features, is equipped with two ISA bus. It is marketed to industrial and military users who have invested in expensive specialized ISA bus adaptors, which are not available in PCI bus versions.

The PC/104 bus, used in industrial and embedded applications, is a derivative of the ISA bus, utilizing the same signal lines with different connectors. The LPC bus has replaced the ISA bus as the connection to the legacy I/O devices on recent motherboards; while physically quite different, LPC looks just like ISA to software, so that the peculiarities of ISA such as the 16 MiB DMA limit (which corresponds to the full address space of the Intel 80286 CPU used in the original IBM AT) are likely to stick around for a while.

As explained in the History section, ISA was the basis for development of the ATA interface, used for ATA (a.k.a. IDE) and more recently Serial ATA (SATA) hard disks. Physically, ATA is essentially a simple subset of ISA, with 16 data bits, support for exactly one IRQ and one DMA channel, and 3 address bits plus two IDE address select ("chip select") lines, plus a few unique signal lines specific to ATA/IDE hard disks (such as the Cable Select/Spindle Sync. line.) ATA goes beyond and far outside the scope of ISA by also specifying a set of physical device registers to be implemented on every ATA (IDE) drive and accessed using the address bits and address select signals in the ATA physical interface channel; ATA also specifies a full set of protocols and device commands for controlling fixed disk drives using these registers, through which all operations of ATA hard disks are performed. A further deviation between ISA and ATA is that while the ISA bus remained locked into a single standard clock rate (for backward compatibility), the ATA interface offered many different speed modes, could select among them to match the maximum speed supported by the attached drives, and kept adding faster speeds with later versions of the ATA standard (up to 133 MB/s for ATA-6, the latest.) In most forms, ATA ran much faster than ISA.

Before the 16-bit ATA/IDE interface, there was an 8-bit XT-IDE (also known as XTA) interface for hard disks, though it was not nearly as popular as ATA has become, and XT-IDE hardware is now fairly hard to find (for those vintage computer enthusiasts who may look for it). Some XT-IDE adapters were available as 8-bit ISA cards, and XTA sockets were also present on the motherboards of Amstrad's later XT clones. The XTA pinout was very similar to ATA, but only eight data lines and two address lines were used, and the physical device registers had completely different meanings. A few hard drives (such as the Seagate ST351A/X) could support either type of interface, selected with a jumper.

A derivation of ATA was the PCMCIA specification, merely a wire-adapter away from ATA. This then meant that Compact Flash, based on PCMCIA, were (and are) ATA compliant and can, with a very simple adapter, be used on ATA ports.

At NIXSYS, we believe in building our relationship with our customers even after our products are delivered. Receiving your PC with ISA Bus on time and getting them up and running is just as important as selecting the right components. We've put together a support team that provides attentive and informed service. Don't hesitate to Contact us with any of your questions.

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