MiSTer FPGA Forum

Hello together,

I am new here in this forum. I have been using MiSTer for about 2 years. And I have connected the MiSTer via a TFT/LED Flat TV (HDMI).Because I am not satisfied with the picture quality of the TFT, I decided to buy a CRT (Sony 27''). This is now connected via VGA->SCART.


My problem now is, that it is not comprehensible which arcade core rotates the screen. Sometimes they are -90°, +90°, -180° or +180°. This is really annoying. It would be nice if you could either configure it globally or if the possibility is registered in the core itself. If I connect the fold over HDMI to the CRT, it turns the screen. In the end I can't turn 60Kg in such a way that it fits the core

BR
MoR33z

This has been asked and explained a number of times before. Video out through analog is exactly what you would get out of the real PCB. To rotate you would need to employ the scaler - which is not a part of the analog video system. These games were designed to be played on monitors that have been roTATEd.

Sorry to say that there is no way to currently rotate the image on the analog video out, and likely will never be available across all arcade cores.

If you're using a PC CRT (31khz) then you can use the scaler and rotate the screen in the menu - the output is good quality.

Also many vertical games have dip switch settings that you can flip or rotate the screen, cocktail mode. I think only a minor amount of games don't have the option. If you choose the right one you hardly have to flip your screen. I use an arcade cab and I felt the pain in the beginning too until i discovered it isn't that bad at all.

ARCADEAGES wrote: ↑Thu Oct 29, 2020 1:22 pm This has been asked and explained a number of times before. Video out through analog is exactly what you would get out of the real PCB. To rotate you would need to employ the scaler - which is not a part of the analog video system. These games were designed to be played on monitors that have been roTATEd.

Sorry to say that there is no way to currently rotate the image on the analog video out, and likely will never be available across all arcade cores.

Thank you verry much. I'm new in this topic especially how the Arcade PCB Video output works.

TwinX wrote: ↑Fri Oct 30, 2020 8:16 am Also many vertical games have dip switch settings that you can flip or rotate the screen, cocktail mode. I think only a minor amount of games don't have the option. If you choose the right one you hardly have to flip your screen. I use an arcade cab and I felt the pain in the beginning too until i discovered it isn't that bad at all.

Hi, i've tested yesterday your suggestion. And yes for some Arcade core there are DIP SW available. But useless (NO FUNCTIONING) in my scenario VGA->SCART (CRT). I have also connected the HDMI cable in parallel. No results at all.

TwinX wrote: ↑Fri Oct 30, 2020 8:16 am Also many vertical games have dip switch settings that you can flip or rotate the screen, cocktail mode. I think only a minor amount of games don't have the option. If you choose the right one you hardly have to flip your screen. I use an arcade cab and I felt the pain in the beginning too until i discovered it isn't that bad at all.

I have now realized that some arcade games of the 90's actually have the option to rotate the screen. This is really great.

MoR33z wrote: ↑Sat Oct 31, 2020 7:28 pm I have now realized that some arcade games of the 90's actually have the option to rotate the screen. This is really great.

Maybe i should have written it better, great that you found it. Enjoy your gaming like i do

MoR33z wrote: ↑Fri Oct 30, 2020 8:49 am

ARCADEAGES wrote: ↑Thu Oct 29, 2020 1:22 pm This has been asked and explained a number of times before. Video out through analog is exactly what you would get out of the real PCB. To rotate you would need to employ the scaler - which is not a part of the analog video system. These games were designed to be played on monitors that have been roTATEd.

Sorry to say that there is no way to currently rotate the image on the analog video out, and likely will never be available across all arcade cores.

Thank you verry much. I'm new in this topic especially how the Arcade PCB Video output works.

Some cores like the GameBoy Advance have a scaling feature so it can be displayed on a CRT, but this is a special feature of the GBA core. From what I understand it would take each arcade board developer to “instrument” the core and hook it up to a scaler - from what I understand is not super easy to do.

Some cores like those from Jotego have built-in H-Position and V-Position soft-adjustment in their cores, which is very nice and much appreciated. I don’t think this works like a scaler however.

ARCADEAGES wrote: ↑Sat Oct 31, 2020 10:52 pm

MoR33z wrote: ↑Fri Oct 30, 2020 8:49 am

ARCADEAGES wrote: ↑Thu Oct 29, 2020 1:22 pm This has been asked and explained a number of times before. Video out through analog is exactly what you would get out of the real PCB. To rotate you would need to employ the scaler - which is not a part of the analog video system. These games were designed to be played on monitors that have been roTATEd.

Sorry to say that there is no way to currently rotate the image on the analog video out, and likely will never be available across all arcade cores.

Thank you verry much. I'm new in this topic especially how the Arcade PCB Video output works.

Some cores like the GameBoy Advance have a scaling feature so it can be displayed on a CRT, but this is a special feature of the GBA core. From what I understand it would take each arcade board developer to “instrument” the core and hook it up to a scaler - from what I understand is not super easy to do.

Some cores like those from Jotego have built-in H-Position and V-Position soft-adjustment in their cores, which is very nice and much appreciated. I don’t think this works like a scaler however.

I have spent the last few days working on the arcade cores and I can only say that the H/V settings as well as the screen rotation are really helpful. Especially with the cores from Jotego this is absolutely great. Thanks for all the work !

MoR33z wrote: ↑Sun Nov 01, 2020 7:35 am
[...]

I have spent the last few days working on the arcade cores and I can only say that the H/V settings as well as the screen rotation are really helpful. Especially with the cores from Jotego this is absolutely great. Thanks for all the work !

Did you get the screen rotation? Because even with that feature built in some cores, I don´t.

Hodor wrote: ↑Mon Nov 02, 2020 11:55 am

MoR33z wrote: ↑Sun Nov 01, 2020 7:35 am
[...]

I have spent the last few days working on the arcade cores and I can only say that the H/V settings as well as the screen rotation are really helpful. Especially with the cores from Jotego this is absolutely great. Thanks for all the work !

Did you get the screen rotation? Because even with that feature built in some cores, I don´t.

Excuse for the delay. For some core it works for some not. It depends if the Arcade Board supports CRT rotation. If you talk only about Arcade. That's why i decided to have more CRT. Depends on the Screen position.....

Is it possible to rotate if we're using direct video HDMI to VGA since it's passing through the HDMI?

https://github.com/MiSTer-devel/Main_Mi ... rect-Video

hyp36rmax wrote: ↑Fri Jun 18, 2021 7:06 pm Is it possible to rotate if we're using direct video HDMI to VGA since it's passing through the HDMI?

https://github.com/MiSTer-devel/Main_Mi ... rect-Video

Nope sorry

VGA monitors have plenty of resolution to use the scaler, which is needed to rotate some cores. From the Analog I/O port use vga_scaler=1. For the HDMI port converted to VGA use direct_video=0 and pick an appropriate video mode (like say a 4:3 one such as 1024x768)

FoxbatStargazer wrote: ↑Mon Jun 21, 2021 10:30 pm VGA monitors have plenty of resolution to use the scaler, which is needed to rotate some cores. From the Analog I/O port use vga_scaler=1. For the HDMI port converted to VGA use direct_video=0 and pick an appropriate video mode (like say a 4:3 one such as 1024x768)

In the HDMI to vga->scart case, Its very difficult to get a proper (viewable) image picking a video mode, when you turn off direct_video

FoxbatStargazer wrote: ↑Mon Jun 21, 2021 10:30 pm VGA monitors have plenty of resolution to use the scaler, which is needed to rotate some cores. From the Analog I/O port use vga_scaler=1. For the HDMI port converted to VGA use direct_video=0 and pick an appropriate video mode (like say a 4:3 one such as 1024x768)

Is there an example of this working?

_javi_ wrote: ↑Tue Jun 22, 2021 1:19 pm

FoxbatStargazer wrote: ↑Mon Jun 21, 2021 10:30 pm VGA monitors have plenty of resolution to use the scaler, which is needed to rotate some cores. From the Analog I/O port use vga_scaler=1. For the HDMI port converted to VGA use direct_video=0 and pick an appropriate video mode (like say a 4:3 one such as 1024x768)

In the HDMI to vga->scart case, Its very difficult to get a proper (viewable) image picking a video mode, when you turn off direct_video

Indeed you are way more limited with TVs. But you can make a custom mode in 240 or 244p and it should show and rotate. (try 1920 wide and in the core set aspect ratio to full) Although rotation will be a bit distorted because its not really enough vertical resolution.

This thread is the top google hit for "MiSTer Rotate CRT", so I thought I'd link it to the partial solution I managed to make in this thread :-
viewtopic.php?p=57523#p57523

It works, the screen is rotated, with scaling artefacts and increased latency, but it's rotated.
If anyone can suggest a better video mode, or a way to lower latency a little, please do chime in on that thread.