Science Fair Project Encyclopedia
XT bus architecture
The XT bus architecture is an eight-bit ISA bus architecture used by Intel 8086 and Intel 8088 systems in the IBM PC and IBM PC XT in the 1980s. It predates the 16-bit ISA architecture used on IBM PC AT machines.
The XT bus has four DMA channels, of which three are brought out to the expansion slots. Of these three, two are normally allocated to machine functions:
| DMA channel | Expansion | Standard function |
|---|---|---|
| 0 | No | dynamic RAM refresh |
| 1 | Yes | add-on cards |
| 2 | Yes | floppy disk controller |
| 3 | Yes | hard disk controller |
See also
- Extended Industry Standard Architecture (EISA)
- Micro Channel Architecture (MCA)
- Peripheral Component Interconnect (PCI)
03-10-2013 05:06:04
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details