Browse Prior Art Database

Personal Computer Feature Card Secondary Bus

IP.com Disclosure Number: IPCOM000109913D
Original Publication Date: 1992-Sep-01
Included in the Prior Art Database: 2005-Mar-24
Document File: 1 page(s) / 48K

Publishing Venue

IBM

Related People

Drerup, BC: AUTHOR [+4]

Abstract

Disclosed is a method that allows a computer system feature card (expansion card) to support the addition of optional functions. The feature card contains a microprocessor and is connected to the host system through a common channel. The optional functions are attached to the feature card through a secondary bus connector. (Image Omitted)

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 89% of the total text.

Personal Computer Feature Card Secondary Bus

      Disclosed is a method that allows a computer system feature
card (expansion card) to support the addition of optional functions.
The feature card contains a microprocessor and is connected to the
host system through a common channel.  The optional functions are
attached to the feature card through a secondary bus connector.

                            (Image Omitted)

      When the microprocessor on the feature card runs a cycle, it
has three possible destinations.  It can access a local device, a
secondary bus device, or a common bus device.  The destination is
determined by the address of the cycle.

      Functions attached via the secondary bus might include a serial
or parallel port, DSP subsystem, data compression processor, etc.
Also, the secondary buses of several feature cards in a system could
be interconnected to form a secondary channel.  The secondary channel
can be used to augment the common channel, without altering the
common channel's standard interface.

      The secondary channel can be used to provide additional
bandwidth for inter-feature card communication and to enable the use
of protocols not supported across the primary channel.  One protocol
that the secondary bus can support is a power management function.
Each feature card can use this bus to indicate its level of power
consumption.  All secondary-bus attached feature cards can then
regulate thei...