Graphic glitch

Responder
Turrican
Mensajes: 131
Registrado: 17 Jul 2016, 18:15

Graphic glitch

Mensaje por Turrican » 04 May 2017, 22:38

Hi.
I'm getting some graphic glitches on some situations.
When I reset the core with Ctrl+Alt+Del or in some games, when it finishes to load or change the screen.

Imagen

Imagen

The first one is when the problem occurs. Many games is being like first screen when finishes to load or in games like Golden Axe in the intro when the screen is changed between the characters one screes appears ok, the other not.

I am using the VGA output.

Regards.

Avatar de Usuario
mcleod_ideafix
Mensajes: 828
Registrado: 27 Sep 2015, 00:14
Ubicación: Jerez de la Frontera
Contactar:

Re: Graphic glitch

Mensaje por mcleod_ideafix » 25 Ago 2017, 10:58

Can you provide me a way of testing this glitch in a consistent manner? I.e. "evertime that I do THIS, the glitch happens".
Also, can you test the last TEST 3 core and see if this still happens?
Thanks!
http://www.zxuno.com
ZX-Uno · Clon de ordenador ZX Spectrum basado en FPGA

Turrican
Mensajes: 131
Registrado: 17 Jul 2016, 18:15

Re: Graphic glitch

Mensaje por Turrican » 25 Ago 2017, 13:31

mcleod_ideafix escribió:Can you provide me a way of testing this glitch in a consistent manner? I.e. "evertime that I do THIS, the glitch happens".
Also, can you test the last TEST 3 core and see if this still happens?
Thanks!
Hi mcleod! I will test in the new core and see if this glitch continue happenning. Great to see a new core of Amstrad!

But everytime that I do a reset (soft reset), it happens. I need to do a lot of resets until the screen goes ok. Or with the ctrl + alt + backspace (doing this, the screen goes ok).
And if you load the game Golden Axe, you can see it too.
During the intro of the game, in the presentation of the characters, you can see the glitch.
Every time that the game changes the character, the glich happens.
Example: first it shows the barbarian - screen ok. Change the character to Dwarf - glitch. Change to woman - ok. Change to Death Adder - glitch.

Regards.

Turrican
Mensajes: 131
Registrado: 17 Jul 2016, 18:15

Re: Graphic glitch

Mensaje por Turrican » 26 Ago 2017, 14:04

Tested.
Same problem. :cry:

Avatar de Usuario
carmeloco
Mensajes: 749
Registrado: 25 Dic 2015, 12:02

Re: Graphic glitch

Mensaje por carmeloco » 26 Ago 2017, 14:15

Yo creo que el problema es que ese monitor, no es capaz de ordenar correctamente los dos campos de vídeo, y a veces los pone al revés.

I think that the problem is the monitor, that can't place correctly the two fields of video, and sometimes, puts they reversed.

Avatar de Usuario
mcleod_ideafix
Mensajes: 828
Registrado: 27 Sep 2015, 00:14
Ubicación: Jerez de la Frontera
Contactar:

Re: Graphic glitch

Mensaje por mcleod_ideafix » 26 Ago 2017, 20:13

Turrican escribió:Tested.
Same problem. :cry:
Yes, tested myself with Golden Axe.

My educated guess is that the CRTC parameters are changed between screenshots in that game and the new parameters confuse the scan doubler. It's not like in the Spectrum, Jupiter ACE or Sam Coupé, in which the screen sync signals remain the same no matter the graphic mode is in use.

Will try to improve the scandoubler for this core :)
http://www.zxuno.com
ZX-Uno · Clon de ordenador ZX Spectrum basado en FPGA

Responder