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Documentation about the Vampire hardware

HDMI Video Resolution & Frequency Problem.

Alexander Gent

Posts 75
24 Mar 2022 22:00


I am trying to setup the screen mode on my Toshiba monitor to display resolution
1360x768 (as per above picture) but all I get is a blank screen.
     
Is there a walk through guide to explain how to setup screen modes?
I have tried to configure the screen modes using the Picasso96 and
PicassoTNG preferences editors but not having much luck.
 
Thank you.


Edgar Fink

Posts 47
25 Mar 2022 08:14


It is a trial and error thing, but I have had luck using "cvt" from aminet: EXTERNAL LINK  or umc:
EXTERNAL LINK 
With umc you can try along these lines to generate a mode line which you can put in to Picasso96 prefs:
umc 1360 768 85500000 -rbt

As far as I remember the rbt option is key here.

This is from memory, so I am not sure the above is correct. Read the docs and rinse and repeat.

There is a thread here you might find useful:
CLICK HERE


Alexander Gent

Posts 75
27 Mar 2022 04:53


Edgar Fink wrote:

It is a trial and error thing, but I have had luck using "cvt" from aminet: EXTERNAL LINK  or umc:
  EXTERNAL LINK 
  With umc you can try along these lines to generate a mode line which you can put in to Picasso96 prefs:
  umc 1360 768 85500000 -rbt
 
  As far as I remember the rbt option is key here.
 
  This is from memory, so I am not sure the above is correct. Read the docs and rinse and repeat.
 
  There is a thread here you might find useful:
  CLICK HERE 

Hi Edgar,
Those utilities were very helpful.
Using PicassoModeTNG I was able install new video screen modes.
Only 2 resolutions didn't work, but I managed to get a nice 1280x720 16bit colour resolution. Nice!

Thank you...


Edgar Fink

Posts 47
28 Mar 2022 08:16


That's cool and you're welcome. You should keep trying with te 1360x768 resolution, I have learned that adjusting the clock rate to below the required by steps of 10 or 5 sometimes work with some monitors.

Did you try the rbt option with umc?


Pat 3657

Posts 50
28 Mar 2022 10:13


Just checking: Is the tool setting OVERCLOCK set to YES ?
If set to NO, Picasso96Mode caps the pixel clock at 50 MHz.
1360x768@60Hz should be possible with a pixel clock around 70 Mhz.

1360x768
Clock: 70.23 MHz
Interlace: no
DoubleScan: no
Framesize: 1460x800
Bordersize: 0x0
Position: 16/2
Syncsize: 64/0
= Frequency 48kHz/60Hz

If this does not work for you, try increasing the framesize and clock (as a bigger framesize decreases frequency below 60 Hz).


Alexander Gent

Posts 75
06 Apr 2022 09:50


Pat 3657 wrote:

Just checking: Is the tool setting OVERCLOCK set to YES ?
  If set to NO, Picasso96Mode caps the pixel clock at 50 MHz.
  1360x768@60Hz should be possible with a pixel clock around 70 Mhz.
 
  1360x768
  Clock: 70.23 MHz
  Interlace: no
  DoubleScan: no
  Framesize: 1460x800
  Bordersize: 0x0
  Position: 16/2
  Syncsize: 64/0
  = Frequency 48kHz/60Hz
 
  If this does not work for you, try increasing the framesize and clock (as a bigger framesize decreases frequency below 60 Hz).

Hi Pat,
The tool setting is set to OVERCLOCK. No matter what I try I can't get the monitor to output to 1360x768 or 1280x768. However it does work with 1280x720.
In the grand scheme, I happy with the results. It is just one of those things...

Thank you.

posts 6