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sorgelig / ZX_Spectrum-128K_MIST

ZX Spectrum 128K for MIST Board
GNU General Public License v2.0
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no display on VGA monitor #3

Closed gorans closed 8 years ago

gorans commented 8 years ago

There is no picture displayed (out of range). Tried three monitors (Vivitron CRT, Syncmaster 192v and TV with VGA). All other MIST cores are working. Old spectrum cores are also working. There is scandoubler_disable=0 in mist.ini.

Best regards, Goran

sorgelig commented 8 years ago

Unfortunately, i don't have monitor supporting VGA 50Hz. I only can test with capture card which is working with ZX Spectrum core in scandoubler mode. Maybe @harbaum can check with his monitor and tell what's the problem.

I guess Vertical sync frequency is too low. If it's true then i cannot do anything here. Actually 50Hz VGA is already beyond of VGA standard.

gorans commented 8 years ago

I think the same but all other PAL cores are working so that's why I posted this Issue.

sorgelig commented 8 years ago

May be core simply doesn't start? Can you try TV mode with scan doubler disabled? Make sure you've put latest spectrum.rom into root of SD card.

gorans commented 8 years ago

Hi,

it was working on the Sony CRT that I sold. That one was displaying all freqs correctly. I tried to connect the TV via VGA->RGB component cable but it’s not working at all, so I can’t double check Speccy core.

Best regards, Goran

On 06.05.2016., at 19:13, sorgelig notifications@github.com wrote:

May be core simply doesn't start? Can you try TV mode with scan doubler disabled? Make sure you've put latest spectrum.rom into root of SD card.

— You are receiving this because you authored the thread. Reply to this email directly or view it on GitHub https://github.com/sorgelig/ZX_Spectrum-128K_MIST/issues/3#issuecomment-217502134

gorans commented 8 years ago

Update: I have saved default settings to Pentagon video, which is not working. After resetting video type to ZX, i have picture.

sorgelig commented 8 years ago

It just proves that your monitor cannot handle all ZX core VSyncs. In ZX mode - there are 311 and 312 lines. In Pentagon mode there are 320 lines, so vertical sync has lower frequency. ~48hz.

sorgelig commented 8 years ago

I recommend to use scaler like this: http://www.aliexpress.com/item/Hot-New-HDMI-and-SCART-to-HDMI-1080P-720-HD-Video-Adapter-Converter/2043816844.html It supports original retro modes.