CRT to VGA

[Dreygor]

Oh my .. ok .. following that project now lol

 

[jassin000]

Taito Scaler can't do scanlines, I need to use a SLG3000 with it to achieve that effect... So its basically better already if it has the same support.

You know what the XRGB2 was really good at (and if I dare to dream hopefully on your device as well) fast mode changes!
Systems like Saturn/Playstation/STV all switch resolutions/modes quickly, 480i to 240p is very common for example (titles screens to game play screens).
This fast mode change will knock a xRGB mini out for almost 5 seconds, the OSSC isn't as bad but still sees a black screen for a few seconds.

 

[twistedsymphony]

You know what the XRGB2 was really good at (and if I dare to dream hopefully on your device as well) fast mode changes!
Systems like Saturn/Playstation/STV all switch resolutions/modes quickly, 480i to 240p is very common for example (titles screens to game play screens).

the PS1 based arcade boards do this often too. System 573, System 12, ZN hardware, etc.

 

[invzim]

Yeah, the xrgb2 is good at 480i - looks like it combines two frames into one using a frame-buffer. I can't do that - but switching isn't terrible. I've since rewritten a bunch of the fpga code for this:
https://www.youtube.com/watch?v=MUx4QuohGdg

skip to about 3 minutes

 

[RealMFnG]

Any chance that will do DOWN-scaling?

I think the OSSC does a good job of up-scaling but other than the UVC there's no good option to convert 31KHz down to 24Khz or 15Khz.

downscaling is useful for things like running Model 2/3 or System 24 on a 15KHz monitor or running Xbox 360, Lindbergh, or TTX on a 24KHz or 15KHz monitor.

+1 person interested in this question's answer.

 

[invzim]

Sorry, I didn't want to hijack this thread. The hardware can do it, but it's not on my list of important features to implement, i.e. focus will be on making the scaler as good and user-friendly as possible first. A couple of issues with down-scaling:

• Output RGB is VGA/console level 75ohm impedance, it does not have the hardware to up it to 5V and 1K impedance for 15khz arcade monitors
• Sync would probably have to be composite

So far see no user-friendly way to swap the mode from upscaling to downscaling - possibly a magic command in the config file on the sd-card. Haven't done the math on 25khz->15khz, 31khz->15khz is just dropping every second line.

 

[jassin000]

So far see no user-friendly way to swap the mode from upscaling to downscaling

I'd love to have one device that has two optional firmwares available, one for downscaling and one for upscaling.
That way you could make the device into whichever solution you wanted by simply flashing the corresponding firmware.

Oh, and even tho I don't personally care... Support for 24khz (in addition to 15khz) mode if downscaling.

• Output RGB is VGA/console level 75ohm impedance, it does not have the hardware to up it to 5V and 1K impedance for 15khz arcade monitors
• Sync would probably have to be composite

First point would be an issue for people looking for downscale, but I believe existing SCART-to-Arcade amps would solve this (user would just need HD15-to-SCART adapter cable).

Sync MUST be composite for downscale folks to display it on a arcade monitor, however just like above the user could simply use a Extron 580 xi to composite separate H/V syncs themselves.

 

[RealMFnG]

Quality downscaling to 15khz and 24khz is what is missing. Sync separators and RGB amps are readily available; would be nice to have these things onboard however.

 

[Dreygor]

Sorry, I didn't want to hijack this thread. The hardware can do it, but it's not on my list of important features to implement, i.e. focus will be on making the scaler as good and user-friendly as possible first. A couple of issues with down-scaling:

• Output RGB is VGA/console level 75ohm impedance, it does not have the hardware to up it to 5V and 1K impedance for 15khz arcade monitors
• Sync would probably have to be composite

So far see no user-friendly way to swap the mode from upscaling to downscaling - possibly a magic command in the config file on the sd-card. Haven't done the math on 25khz->15khz, 31khz->15khz is just dropping every second line.

Hijack away! This is the device/info I was looking for

 

[SNK-NEO-GEO]

@invzim - focusing on the upscaler first is a great idea.. maybe down the road you can focus on a new downscaler device with scart and components output or whatever makes sense. Maybe we can outsource a UVC and send it your way for reverse engineering and improve on that model since the UVC seems to be the best downscaler out there but hard to get.