[Tfug] where are my terminals?

[Adrian]

On Tuesday 01 August 2006 00:18, Earl wrote:
[snip] 
> Interesting sidelight. Using Sun mono-sync monitor with 1152x900
> resolution and 76 KHZ sync. KDE picked up the 1152x900 but uses a 30
> KHZ sync and won't allow me to change it. Works fine and no smoke yet
> so I am sticking with it.
> 

Hmmm... but which sync value are you looking at? You say kHz (kilo-Hertz), but 
that is way to fast for any vertical monitor sync. A typical vert. sync would 
be 60-125Hz, the rate at which a complete vertical screen is drawn. According 
to Sun, a Monosync GDM 17E10 is 1152x900 at 76Hz vert. sync (with an optional 
1152x900 @ 66Hz mode). You should have atleast 60Hz vert. sync, anything less 
is visibily noticable to most users, a 30Hz vert. sync would be horribly 
"flashy" to any user.

Now the horizonal sync, on the other hand, is a completely different beast and 
is in kHz. The horz. sync is a function of the vertical sync rate and the 
total number of lines drawn on the screen (there is a horz. sync at the end 
of each line sweep). Typical horz. sync rates are in the range of 25-100kHz. 
You don;t set the horz. sync directly, just the outer limits for the monitor.

Given a vert. sync of 76Hz at 900 (plus a few overscan) lines, you would end 
up with a horz. sync of ~70kHz, ~35kHz in interlaced mode. Now at the 66Hz 
optional mode, you would get a horz. sync of ~60kHz, 30kHz in interlaced 
mode.

So, if you really have a 30kHz horizontal sync, it sounds like you are really 
running 1152x900 @ 66Hz in interlaced mode.


Adrian