Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!ihlpf!gmd1
From: gmd1@ihlpf.ATT.COM (Doughty)
Newsgroups: comp.sys.ibm.pc
Subject: Re: IBM EGA problems
Summary: horizontal retrace
Message-ID: <3704@ihlpf.ATT.COM>
Date: 16 Feb 88 14:51:57 GMT
References: <207@ritcv.UUCP>
Organization: AT&T Bell Laboratories - Naperville, Illinois
Lines: 36

In article <207@ritcv.UUCP>, kfk9673@ritcv.UUCP (Karl Kingston) writes:
> Hi Everybody.....
> 
>     I have 2 problems with my EGA setup.  
> 
> 1)  When I start up my EGA in Enhanced Color Mode, the 1st character is
>     reversed, blown to double width.  The 2nd character is 1/2 it's size
>     and all other characters are normal.  In Normal Color Mode, the EGA
>     monitor works fine.  I am under the impression that the raster guns are
>     "bouncing" off the side of the tube.  ...
> 
>	<second question omitted since I don't know answer>
> 
> Any info would be *GREATLY* appreciated.
> 
> Thanks..
> Karl Kingston
> 

No, the raster guns are not bouncing.  The problem is that the board
begins to display the characters while the monitor is still moving
the beams back to the left side of the screen (call horizontal retrace).
Since this horizontal retrace is right to left, any characters displayed
at this time will be reversed.  Also, the horizontal retrace is much
faster that the left to right motion.  Hence any characters displayed
during this time will also be bigger.  With regard to the second
character, the beams appear to have just barely reversed direction at
that point and are not yet scanning at the normal speed.

Assuming the monitor has some adjustments you could try tweeking
the horizontal hold or horizontal size to see if that will resolve
the problem.  I would stay away from any horizontal linearity adjustment
however.

Greg Doughty
ihnp4!ihlpf!gmd1