< hardware , architecture > (After the IBM PC XT ) 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 the Intel 80286 based 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 disc controller
(1997-09-15)