82091AA Datasheet, PDF (8/204 Pages) Intel Corporation – ADVANCED INTEGRATED PERIPHERAL (AIP)

82091AA
1 0 OVERVIEW
The major functions of the 82091AA are shown in Figure 1 A brief description of each of these functions is
presented in this section
Host Interface
The 82091AA host interface is an 8-bit direct-drive (24 mA) ISA Bus X-Bus interface that permits the CPU to
access its registers through read write operations in I O space These registers may be accessed by pro-
grammed I O and or DMA bus cycles With the exception of the IDE Interface all functions on the 82091AA
require only 8-bit data accesses The 16-bit access required for the IDE Interface is supported through the
appropriate chip selects and data buffer enables from the 82091AA
Figure 2 shows an example system implementation with the 82091AA located on an ISA Bus add-in card This
add-in card could also be used in a PCI-based system as shown in Figure 3 For motherboard implementa-
tions the 82091AA can be located on the X-Bus as shown in Figure 4
Figure 2 Block Diagram of the 82091AA on the ISA Bus
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