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From: peter@graffiti.UUCP (Peter da Silva)
Newsgroups: net.micro.pc
Subject: Re: New color card: 256 colors on a PC!
Message-ID: <242@graffiti.UUCP>
Date: Tue, 24-Sep-85 18:21:25 EDT
Article-I.D.: graffiti.242
Posted: Tue Sep 24 18:21:25 1985
Date-Received: Sun, 29-Sep-85 05:41:36 EDT
References: <7700013@prism.UUCP> <372@bbncc5.UUCP>
Organization: The Power Elite, Houston, TX
Lines: 18

> No, on a color composite video monitor or analog RGB display.  It's
> impossible to display more than 16 colors on an IBM-CGA-compatible
> monitor or 64 colors on an Enhanced Color Display: the RGB signals
> are digital, not analog, and there are only 4 separate inputs 
> (or 6, for the ECD).  

Infoworld, Sep 16 1985:

    A new graphics board from a division of AT&T lets standard IBM-PC color
    displays produce images with as many as 256 colors simultaneously, 32 times
    the existing limit... [it] overcomes the inherent limit in the current
    digital RGB monitor...

    "We're using a technique patented by Bell Labs several years ago to increase
    the number of colors. It's a form of pulse-width modulation that tricks the
    monitor into thinking it has more than 1 level for each component."

The board is called the VDAD, for Visual Display Adapter/Digital.