TITLE
    Multiple Scan 17 Display: DOS Card Requires Adapter (8/94)
Article ID:
Created:
Modified: 		16122
8/29/94
5/24/95
TOPIC



    I have connected an Apple Multiple Scan 17 Display to a Macintosh Quadra 610 with the DOS compatibility card. When I try to switch from the Macintosh to the DOS environment, the screen fades slightly, but system freezes and never switches to DOS. On the PC Setup control panel only the 16-in and VGA options are available. It seems like that Macintosh recognizes the monitor as an Apple 16-in display.

    Is the Apple Multiple Scan 17 Display compatible with DOS Compatibility Card? If the answer is yes, which resolutions are supported in the Windows or DOS applications, and which is the correct configuration to make it work?

DISCUSSION


    The sense pins on the Multiple Scan 17 Display signal the Macintosh that a 14-in. monitor is connected and the Macintosh sets up the video signal up for a 14-in. display. However when the video software loads and queries the monitor, it determines that it is really a 17-in. display, and re-sets the video accordingly.

    The problem on the Quadra 610 DOS compatible is that the initial video setup is sent to the DOS Compatibility Card, and so the card is set incorrectly for that monitor. The Macintosh video software has no access to change the parameters that were previously set in the DOS compatibility card.

    Workaround
    -----------
    The only workaround is to configure the sense pins on the monitor for a Apple 16-in. display. This allows the Macintosh to correctly set the DOS compatibility Card video parameters at startup. There are two vendors that sell adapters that allow you to configure the sense pins on the monitor; James Engineering and Enhance Cable Technology.

    Once you have attached the proper cable adapter which sets the sense pins for a 16-in. display, the DOS compatibility card supports all 16-in. resolutions. A complete list of these resolutions is available in the Technical Information Library article titled "DOS Card: Video Modes Supported".

    To locate a vendor's address and phone numbers, use the vendor name as the search string.


    Support Information Services


Document Information
Product Area: Monitors-Displays
Category: Multiple Scan Displays
Sub Category: Multiple Scan 17 Display
Keywords: kcompat, kwindows

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