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Mail Archives: djgpp/1997/08/14/04:57:49

Date: Thu, 14 Aug 1997 20:59:58 +1100
From: Bill Currie <billc AT blackmagic DOT tait DOT co DOT nz>
Subject: Re: mistake in COLOR enum in conio.h
In-reply-to: <33F220F2.11F4@cam.org>
To: Vic <tudor AT cam DOT org>, djgpp AT delorie DOT com
Message-id: <199708140904.VAA11640@teleng1.tait.co.nz gatekeeper.tait.co.nz>
Organization: Tait Electronics Limited
MIME-version: 1.0
Comments: Authenticated sender is <billc AT blackmagic DOT tait DOT co DOT nz>

On 13 Aug 97 at 17:02, Vic wrote:

> light red ?? is there any hardware reason for the light/dark gray
> stuff 

Yes, the lower 4 bits of the color number represent the `settings' of 
the electron guns (for cga): IRGB (I=bit 3 and B=0). I (for 
intensity) selecects whether or not the guns are at half or 
full power.

However, I can only guess that the reason 0b1000 (8) is dark grey 
rather than black is the I bit adds a voltage to all three guns 
rather than acting as a multiplier.

Bill
--
Leave others their otherness.

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