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More VRAM

Posted: Mon Oct 26, 2020 8:50 pm
by Fenner Machine


More VRAM would be nice.


I know it’s possible to work around some limitations of 128KB VRAM, or it even inspiring creativity, and maybe that’s half the fun.


But, more dedicated VRAM in VERA would make it easier to have larger bitmaps & tile maps, more animations & tiles, larger sprites, and take advantage of the native 640×480 resolution and 256 colour mode.


More VRAM

Posted: Mon Oct 26, 2020 9:15 pm
by TomXP411

This has been discussed, and I believe it's not actually possible with the current FPGA being used for VERA. 

The memory in VERA is dual port RAM and is part of the FPGA package. Using external memory for the FPGA would require much larger and more expensive components - potentially costing more for just the video hardware than the current price target for the entire system.

** update

@Frank van den Hoef is the designer of VERA, so he might be able to shed more light on the hardware and its capabilities.

 

 


More VRAM

Posted: Mon Oct 26, 2020 9:23 pm
by Fenner Machine


OK, that makes sense.


I did a search and found discussions of VRAM limitations, but not about why it can’t or won’t be increased.


Work within the limits and use workarounds, gotcha.


More VRAM

Posted: Tue Oct 27, 2020 12:30 am
by TomXP411


3 hours ago, Fenner Machine said:




OK, that makes sense.



I did a search and found discussions of VRAM limitations, but not about why it can’t or won’t be increased.



Work within the limits and use workarounds, gotcha.



I think the conversation was on the Facebook group, but I can't find the specifics there, either. (FB is terrible about losing conversations.)

Hopefully, Frank will chime in with which FPGA is being used and why he chose that particular model. 


More VRAM

Posted: Mon Feb 08, 2021 1:18 pm
by Lorin Millsap
I don’t know if Frank has seen this or not but in the conversations about why the specific one was choosen, a couple big items.

It was chosen because it is low cost with a large amount of RAM in it. If you look at most FPGAs that have large RAM they are almost always big expensive FPGAs. In the same product line there was another FPGA that had double the RAM but it was way more costly and was a BGA chip which would require outside manufacturing to assemble. This is bad for low volume test modules which are needed to even develop the system and none of us have the capability to handle those in house.

Needless to say the VERA we have designed now is what we are sticking with. Limitations and all. It is for programmers to work with the systems limitations and either adjust the design to fit, or figure out clever tricks to work around them.


Sent from my iPhone using Tapatalk

More VRAM

Posted: Mon Feb 08, 2021 1:51 pm
by AndyMt


33 minutes ago, Lorin Millsap said:




It is for programmers to work with the systems limitations and either adjust the design to fit, or figure out clever tricks to work around them.



I love this aspect! VERA offers quite a lot more than my ATARI ST did back then. And as the 6502 CPU is not that powerful, more VRAM or capabilities would not be feasible to handle. Looking at what I was able to achieve even with my very first 2 games, I'm very happy with this. It's hard enough to be a challenge and capable enough to provide impressive results.

I'm now thinking about palette switching on certain scan-lines for my next game in order to show more than 256 colors. I'm curious how that goes.