MEGA65 FORUM

Questions about the graphic resolution

append delete ZeHa

Hi,

I have heard the MEGA65 has a maximum resolution of 1920x1200. I understand that it might be necessary to have this 16:10 resolution, but in general, I am not so happy about this, because this means you have to use a special monitor for the MEGA65. With 1920x1080, it would be possible to hook it up basically anywhere. Luckily I have a 1920x1200 monitor, but still, I think it's a bit sad.

On the other hand, I am not so interested in this high-res mode anyway. So how about the low-res modes? What happens if you use the MEGA65 in plain C64 mode? What resolution will it output? Will it only be possible to use it via HDMI? Or will there also be VGA or Composite out? I am very interested in the MEGA65, but if I can only use it with HDMI on a 1920x1200 monitor, my interest gets a bit narrow, sadly. So it would be nice if you could clarify this a little.

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append delete #1. MIRKOSOFT

As first - currently Mega 65 runs on Nexys4DDR and this FPGA has as standard VGA 12-bit output.
Second: Look at resolution common for many Commodore 8-bits: AR is 16:10 or 8:5 - when you look at VIC2(E) and VIC3 - 320x200, 640x400, 1280x400 (in double height) even standard VDC 640x200 (double height)... When you look at character set - always the same 8:5 or 16:10. I mean when will be Mega 65 finished it will support any up/down scaler.
I'm using with Nexys4DDR 16:10 LCD and for capture AV downscaler to 1440x900...
Miro

append delete #2. ZeHa

I understand that many of the old resolutions are in 16:10, but that's not the point here. I have to be able to use the MEGA65 with a modern TV, and if I am using 320x200 mode, I would expect the MEGA65 to output something that my TV can handle, and I wonder what this would be. There are many possibilities what COULD happen, some of them might include stretching or letterboxing or something. But right now I wonder what ACTUALLY happens when the current MEGA65 tech is connected to a modern TV or other hi-res monitor and a low-res mode like 320x200 is used.

append delete #3. MIRKOSOFT

Really Nexys4DDR has 12-bit VGA output. That's now, of course as prototype. Image is pretty clear and color identical. Output produces 1920x1200 analog signal, but true is that up/down scalers damaging the picture.
Each Q in resolution excludes borders, forgot you?
This means that Nexys4DDR displays not working area in whole 1920x1200 - it can scale 320x200 and borders will be different in 16:10 - 16:9 - 4:3 etc.
When you connect your C64 to old 4:3 TV (really old) you'll see that visible border is more high.
When you connect to modern digital 1080p border will be less high. Of course current digital TV or LCD allows stretch, native, fill image formats. I mean border is nice handled in demos, but is not useful normally. Other situation is in case C128's VDC - it has no border and there can be problem, but Mega 65 has common with C128 only 64 mode, so it doesn't matter. Yes, I'm really 128er and sadly looking at M65 which maybe anytime will support C128 mode with its 2 desktops and 2 CPUs...
I mean solving resolution can be leave user to scale C64 or C65 image by device, but it solves not M65 new modes...
Miro

append delete #4. gardners

MEGA65 does currently do 1920x1200 @ 60Hz. We understand that this is really annoying for many people, and expect that we may move to 1080p @ 50Hz. This is on our TODO list, but is not currently at the top. Fixing 6502 illegal opcode support, and C65 bitplanes are the tasks currently taking my focus.

append delete #5. Pixman

Hi, I wondered about those graphics modes.

With only 128kb of RAM, how are we supposed to program these high-res modes? :7

Or how is this solved?

Thanks,
Pixman

append delete #6. LoveMega65

@Pixman

Are you saying that the 128KB RAM is a blocking stone to preventing us to program high-res modes?

append delete #7. ZeHa

can't the normal (low) resolutions just be scaled up 5 times (to 1600x1000) and then displayed with a border instead of scaling up to 1920x1200 and killing 1080p compatibility?

to be honest i am not really interested in the REAL hires mode anyway, and i really wonder who might use that. i think the normal low res modes are perfectly fine, it should only be possible to display those cleanly on a hires (1080p) display instead of letting the TV upscale that for you (with unpredictable results)...

append delete #8. gardners mobile

Hello,

We already gave hardware scaling to use such old modes scaled up. we expect that when done it won't be a problem to do something equivalent to what you want.

Paul.

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