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From: dalegass@dalcsug.UUCP (Dale Gass)
Newsgroups: comp.sys.ibm.pc
Subject: Re: How does one enable the other 8 background colors
Message-ID: <108@dalcsug.UUCP>
Date: Sun, 5-Jul-87 12:07:55 EDT
Article-I.D.: dalcsug.108
Posted: Sun Jul  5 12:07:55 1987
Date-Received: Sun, 5-Jul-87 22:35:53 EDT
References: <292@qtc.UUCP> <1005@watmum.UUCP> <1982@druhi.ATT.COM>
Organization: Dalhousie University, Halifax, N.S., Canada
Lines: 34
Summary: How to enable the intensified colors

In article <1982@druhi.ATT.COM>, bryan@druhi.ATT.COM (BryanJT) writes:
> 
> This isn't quite true.  Bit 5 of the "Mode Select Register" of the 6845
> CRT controller (used in the IBM CGA and many clones) selects blinking
> versus 16 background colors.  Doing:
> 
> 	MOV DX,03D8H
> 	OUT DX,009H
> 
> on an IBM PC with CGA will cause 80x25 color text mode to be selected
> with 16 background colors and no blinking.  In this mode, setting what is
> normally the "blink" bit will now intensify the background color, giving
> you access to the other 8 background colors.  The ROM BIOS merely sets

Although the following doesn't work on my cga-clone, the IBM manuals say
that bit 4 of register 3d9 will 'Intensify the background colors in the 
alpha mode'.  Thus, an  MOV DX,03d9h   MOV AL,10  OUT DX,AL should allow
the use of the other 8 background colors (but not all 16 at once).

-dalegass@dalcsug.uucp








gotta include more new text than old text...




gotta include more new text than old text...