Browse Prior Art Database

Hot plug design

IP.com Disclosure Number: IPCOM000005023D
Publication Date: 2001-Jul-17
Document File: 4 page(s) / 72K

Publishing Venue

The IP.com Prior Art Database

Abstract

Disclosed is a design for the implementation of the Hot Plug requirement of the Display Visual Interface 1.0 Specification. Benefits include compliance with the DVI standard, ease of localization by the automatic display of property pages when a display device is connected or detached, and improved user satisfaction.

This text was extracted from a WORD97 document.
This is the abbreviated version, containing approximately 79% of the total text.

Hot plug design

Disclosed is a design for the implementation of the Hot Plug requirement of the Display Visual Interface 1.0 Specification. Benefits include compliance with the DVI standard, ease of localization by the automatic display of property pages when a display device is connected or detached, and improved user satisfaction.

The Display Visual Interface 1.0 Specification (DVI 1.0) defines the capabilities and interfaces for DVI 1.0 compliant digital display devices. One key requirement is the automatic detection of the attachment or detachment of digital display devices. A feature that meets this requirement is called a Hot Plug. The implementation of this feature is not described in the DVI specification. The disclosed design is one implementation that meets the DVI requirements.

Components

The disclosed design is included in a graphics software driver. Other components that are also used include:

AIM 3.0 compliant TMDS transmitter driver module

System BIOS

DVI1.0 compliant hardware

Host

Transmitter

Display

Hot Plug supported digital display.

Algorithm (Usage Model)

When a system is booted and running an operating system, the end user may exercise any one of several scenarios.

Attach a digital display (in addition to an existing display on which the system has booted)

From an end user perspective, the additional display should display an image. Additionally, the end user may also want to tailor the new display to show the image full screen or edit the color depth. These secondary functions are performed by opening up the display property pages to customize the look and feel of the newly connected display.

Detach a digital display (in addition to an existing display on which the system has booted)

From an end user perspective, the additional display should blank out while the system continues to display data on the connected display.

Attach a digital display (this is the only display)

From an end user perspective, this display should instantly (almost) display an image. The only difference in this scenario is that the system is not forced to manage certain limitations such as bandwidth, refresh rates, resolution ... when there was also an additional display connected in the system.

Detach a digital display (single display)

From an end user perspective, the additional display simply blanks out.

Design Details

When the system has booted an operating system and a digital display is attached (in addition to an existing CRT), the following sequence occurs (see Figure 1):

1. The newly connected display notifies the system Host of the connection event (usually via a transmitter, such as a TMDS transmitter).

1. The Host hardware informs the Hot Plug interrupt handler, triggering the Hot Plug Interrupt routine.

2. The driver communicates with the display ...