Browse Prior Art Database

Bus Prototype Circuit Card for Personal Computers

IP.com Disclosure Number: IPCOM000099596D
Original Publication Date: 1990-Feb-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 2 page(s) / 49K

Publishing Venue

IBM

Related People

Curtis, BA: AUTHOR [+2]

Abstract

A technique is described whereby an interface bus prototype circuit card provides address interface capability to personal computers, such as the IBM Personal System 2* (Models 50, 60 and 80) and attachment devices.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Bus Prototype Circuit Card for Personal Computers

       A technique is described whereby an interface bus
prototype circuit card provides address interface capability to
personal computers, such as the IBM Personal System 2* (Models 50, 60
and 80) and attachment devices.

      The circuit card is designed to operate in the 300-31F (Hex)
input/output (I/O) address range.  The circuit presents either eight
or sixteen bits of buffered data to the user, as shown in the block
diagram.

      In prior art, prototype circuit cards have been developed for
the Advanced Technology (AT*) type of personal computers.  As in the
AT prototype cards, a jumper should be installed for word transfers.
Byte High Enable is an additional qualifier used to enable the upper
byte bidirectional buffer.  Channel Size 16 is generated by decoding
the address lines and memory/-I/O.

      The address lines are latched via the Address Latch Enable and
the Status Lines, and the Memory/-I/O is decoded into I/O read and
write lines.  Therefore, the Status and Address lines are used as
qualifiers, and the -CMD (Command Line) is used to enable the
bidirectional buffers.

      It is significant to note that the concept is not restricted to
just the eight- and sixteen-bit structure, but the same concept can
be used in extended bit structures, such as thirty-two-bit
structures.
* Trademark of IBM Corp.