VERA Stand-alone board

[Jay Crutti]

I remember in the early days of the X16 project it was mentioned that the VERA would be offered as a standalone board that could be used with other systems, new and old. Since that time I've seen some forum posts saying that may have changed and now its not going to be released for other systems to use, open source or not. Can anyone confirm this change in stance?

I ask because I'm experimenting lately with a NABU system and am getting very annoyed with how limited and low quality the TMS9918 VDP chip is, and that got me thinking how silly it is that in 2023 we're still trying to work around old technology chips and limits (4:3 only, limited colors, composite video with NTSC artifacts, etc,.) that have been superseded long ago. It looks like the VERA is a modern platform that avoids most of these problems, but not sure if it will still be shared with the world outside of the X16. I know Ben Eater has a fun little VGA implementation too, but it seems the VERA is clearly the superior design so I was wondering if it might be a possibility in the future. I've also bought one of the F18A boards, but that's a reimplementation of the old technology with only some of the most annoying problems fixed with the VGA output. VERA is clearly a major step forward beyond that.

Thanks, and looking forward to your replies.

[TomXP411]

now its not going to be released for other systems to use, open source or not. Can anyone confirm this change in stance?

Frank did open-source VERA, but there's no indication that he plans to build a VERA cartridge for the C64, for example. I'd proceed under the assumption that if you want a VERA cartridge, you will either need to design one or talk someone into designing one.

I believe there was a VERA test harness in the early days, but I'm unclear if this used a parallel interface or a serial interface used, like the Gameduino that inspired VERA.

I actually want a VERA standalone, too - to use with my Ultimate 64. As it is, the U64 is pretty amazing, but I really want an 80-column display, and VERA is the perfect solution for that.

[Ender]

I ask because I'm experimenting lately with a NABU system and am getting very annoyed with how limited and low quality the TMS9918 VDP chip is, and that got me thinking how silly it is that in 2023 we're still trying to work around old technology chips and limits (4:3 only, limited colors, composite video with NTSC artifacts, etc,.) that have been superseded long ago. It looks like the VERA is a modern platform that avoids most of these problems,

Just so you know, the VERA has limitations also. It only supports 640x480 at 60Hz. You can zoom in with it, to get smaller resolutions, but not bigger. At 640x480, however, there isn't much VRAM for graphics, so most things that use VERA will be at lower resolutions. Color only goes up to 8-bit, but at 640x480 I think there's only enough VRAM for 2-bit color (and that's just 1 frame).

[Jay Crutti]

Just so you know, the VERA has limitations also. It only supports 640x480 at 60Hz. You can zoom in with it, to get smaller resolutions, but not bigger. At 640x480, however, there isn't much VRAM for graphics, so most things that use VERA will be at lower resolutions. Color only goes up to 8-bit, but at 640x480 I think there's only enough VRAM for 2-bit color (and that's just 1 frame).

Ahh, that's unfortunate but thank you for enlightening me. If I had my dream retro video card, it would natively support 16:9, support 8 bit color depth, support up to 1080p or 720p, and support sprites and all that goodness. Guess I'll need to try to convince someone smarter than me to take on the challenge of designing one. Thanks for everyone's help.

[Jestin]

At 640x480, however, there isn't much VRAM for graphics

I don't know if that's really a fair assessment, given that the VERA has 128k of video RAM. That's twice as much RAM just for video than the C64 had for everything. You aren't going to be displaying a 640x480x8bpp bitmap, but you can absolutely do 2 layers of 16x16x8bpp tiles on a scrolling screen that is 128x64 tiles in size, using 256 individual tiles in the set. I know this because with a single line change, I'm staring at my own game running in this mode right now.

640x480.png (242.92 KiB) Viewed 5764 times

Unless I'm mistaken, this is pretty much unheard of for an 8 bit system.

What I've learned is that you can choose which way to limit yourself. You can restrict the number of tiles in your set, or you can go down to 4bpp/2bpp modes, or you can shrink your playfield and replace tiles on the fly, or any other number of tricks to fit more graphics in a limited space. But still, I'd hardly say that 128k isn't much VRAM.

[StephenHorn]

Unless I'm mistaken, this is pretty much unheard of for an 8 bit system.

640x480 wasn't even really a thing until IBM launched the first VGA adapters in 1987, and even then was mostly restricted to text modes. I'll grant that the video chipset on the IBM PS/2 had 256KB of memory, as opposed to VERA's ~128KB, and the VGA standard provides some help from the video chipset to blit data between sections of VRAM, which the VERA can't so easily do.

But, look, even Super NES games (1990+) usually used the standard resolution of 256x224, and the Sega Genesis/Mega Drive (1988+) was only nominally better at 320x224. Sony Playstation (1994+) could only reach 640x480 in interlaced modes. The Nintendo 64 (1996+) could reach 640x480, but most games that used it required the Expansion Pak add-on and were not super performant when it came to their framerate (Perfect Dark, anyone?). You pretty much have to go to the Sega Dreamcast (1998+) to start seeing 640x480 on game consoles. Bearing in mind, this was the era of CRTs and you could only get so much fidelity

I like using game consoles and games as a point of comparison because for many generations, those defined the graphical capabilities and limitations that they experienced. I think my first experience with a 640x480 bitmap display might've been Windows 3.11, no earlier than 1994. But I guess my point is that this is solidly into the "16-bit" era, starting into the "32-bit" era, and it's important to remember that the X16 is, in spite of the `16`, intended to be an 8-bit system, at heart.

[Ender]

True. I wasn't trying to say it was bad or I didn't think it was enough, just that most things written for the VERA probably won't even be 640x480, let alone more modern resolutions (which it physically can't do).

[BruceRMcF]

Just so you know, the VERA has limitations also. It only supports 640x480 at 60Hz. You can zoom in with it, to get smaller resolutions, but not bigger. At 640x480, however, there isn't much VRAM for graphics, so most things that use VERA will be at lower resolutions. Color only goes up to 8-bit, but at 640x480 I think there's only enough VRAM for 2-bit color (and that's just 1 frame).

Ahh, that's unfortunate but thank you for enlightening me. If I had my dream retro video card, it would natively support 16:9, support 8 bit color depth, support up to 1080p or 720p, and support sprites and all that goodness. ...

1080p at 16:9 at 8bit color depth is 2MB of data. That is well out of the amount of data you'd want an 8bit CPU to be slinging around, so now you are talking probably a 32bit era or higher tier of system.

For pure tile and sprite graphics, 640x480 and an 8bpp color palette is an upgrade on the video displays of the 8bit era, and for bitmap graphics, 320x240 with 16 colors from 8bpp is a lot less taxing on the processor.

[Fabio]

Besides the resolution discussion a vera card for the XT class machines would allow tile based games: saving a lot of work to the cpu.
And let's not forget the audio since the majority of early PCs had only a poor speaker.