Browse Prior Art Database

Self-Identification Protocol Initialization

IP.com Disclosure Number: IPCOM000119957D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 2 page(s) / 78K

Publishing Venue

IBM

Related People

Butler, ND: AUTHOR [+2]

Abstract

A method whereby a monitor and display adapter can determine whether the other supports a self-identification protocol is described.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Self-Identification Protocol Initialization

      A method whereby a monitor and display adapter can
determine whether the other supports a self-identification protocol
is described.

      When a self-identifying monitor is powered on, it must set
itself up to behave like an existing conventional monitor (sending
Monitor ID and responding to relevant syncs) in order to support
conventional display adapters. The software for a self-identifying
display adapter must also be able to find out if a
self-identification monitor is attached in order to know how to set
up the adapter.  The self-identifying communication is made down the
same pins as the Monitor ID (to save pins) and so there must be a
way for the monitor and adapter to find out if each can support
self-identifying communication.

      This disclosure covers the mechanism by which a monitor and
display adapter recognize one another as capable of self-identifying
communication and release the Monitor ID wires to be used as the
physical communication channel. When initially powered-on, a
self-identifying monitor must emulate an existing conventional
monitor type so as to be compatible with conventional adapters.  If a
self-identifying adapter is in use, then the software driving that
adapter needs to find out if a self-identifying monitor is attached.
If a self-identifying monitor is attached, then the software will
find out the monitor characteristics, and program the adapter
accordingly.  If the attached monitor does not support
self-identifying communication, then the adapter software will
program the adapter appropriately according to the Monitor ID.

      To determine whether self-identifying communication is
possible, the adapter and monitor perform the following steps.  The
adapter is the master of this operation,...