Palettemate / enhanced video ULA with 4096 colours

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Elminster
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Re: Palettemate / enhanced video ULA with 4096 colours

Post by Elminster » Sat Jun 09, 2018 8:02 am

tricky wrote:
Sat Jun 09, 2018 6:21 am
As you can set the palette and then run any existing game, everything is supported.

The latest version of b-em supports it if you want to "try before you buy"
Yes indeed I had one of the first Nula’s.

But what I was looking for was a list of stuff people had actually enhanced, I was thinking of ideas for schools (to be posted in another post when I get around to it). And a videonula game machine sprung to mind. But due to limited time (same as most) I don’t want to either reinvent any wheels or put in lots of pallete changing effort.

So hence the question about a list, so I guess you and Rob have just started the list. :)

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by Elminster » Sat Jun 09, 2018 8:05 am

RobC wrote:
Sat Jun 09, 2018 7:37 am
Just to add to tricky's summary, I've modded Killer Gorilla, Hunchback and Dare Devil Denis to use 16 colours. Stewart (sbadger) modded Galaforce.

I've tried to put the demos and modded games in the support pack but it needs updating as it's missing Frogger and a couple of other demos.
So the list is in effect the demo pack at the moment + frogger. That could be enough for what I sort of hand in mind.

We need the videonula prince or persea :)

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by RobC » Sat Jun 09, 2018 10:13 am

Elminster wrote:
Sat Jun 09, 2018 8:05 am
We need the videonula prince or persea
That would be awesome!

I have another demo/project on the go but it's in the very early stages. Feel free to PM me if you want more details :wink:

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by RobC » Fri Jun 15, 2018 10:46 am

RobC wrote:
Sat Jun 09, 2018 7:37 am
I've tried to put the demos and modded games in the support pack but it needs updating as it's missing Frogger and a couple of other demos.
I've finally got round to updating the support pack. I've included the MMC compatible versions of the Bitshifters gallery demos, the updated Spectrum emulator and tricky's NULA enhanced Frogger. The link is still: https://tinyurl.com/y75cmrxe

(Don't be put off by the February 2018 in the name - I kept it like that to ensure Dropbox preserved the link.)

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by sbadger » Thu Jun 21, 2018 9:23 am

RobC wrote:
Fri Jun 15, 2018 10:46 am
RobC wrote:
Sat Jun 09, 2018 7:37 am
I've tried to put the demos and modded games in the support pack but it needs updating as it's missing Frogger and a couple of other demos.
I've finally got round to updating the support pack. I've included the MMC compatible versions of the Bitshifters gallery demos, the updated Spectrum emulator and tricky's NULA enhanced Frogger. The link is still: https://tinyurl.com/y75cmrxe

(Don't be put off by the February 2018 in the name - I kept it like that to ensure Dropbox preserved the link.)
Hi Rob, that's the old version of galaforce in the pack, there is a newer one with nula loading screen in the thread.
viewtopic.php?f=1&t=13762&p=186547
stew
So many projects, so little time...

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by RobC » Thu Jun 21, 2018 9:49 am

sbadger wrote:
Thu Jun 21, 2018 9:23 am
that's the old version of galaforce in the pack, there is a newer one with nula loading screen in the thread.
Ah - sorry I missed that (and it's a great loading screen too!). I've now updated the pack to include the latest version.

It's available under the same link.

Thanks,

Rob
Last edited by RobC on Thu Jun 21, 2018 9:50 am, edited 3 times in total.

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by Elminster » Sun Sep 02, 2018 9:57 pm

Random thought.

If all the 'enhanced' features of videonula were hacked out, could you lose any of the hardware/reduce costs and would it be 100% backwards compatiable. What I am sort of saying is how hard/cost would it be to produce a VULA replacement as opposed to the endhance version.

Might have benn asked before, in which case I just asked again!

I was think about the idea behind Roland's Atom, and trying to keep parts as original as you can, for the Beeb equiv the best bet for realness would be to have a ROM slot that you could drop in a original ULA, and enhanced ULA or the middle ground a non enhanced ULA (CPLD).

Not sure if my rambling make sense, made sense in my head.

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by RobC » Mon Sep 03, 2018 8:20 am

Elminster wrote:
Sun Sep 02, 2018 9:57 pm
If all the 'enhanced' features of videonula were hacked out, could you lose any of the hardware/reduce costs and would it be 100% backwards compatiable.
I think it would probably only reduce the component count slightly as you would only really lose the 12 resistors from the DACs. It may be possible to use a slightly cheaper CPLD - I chose the EPM570 as I wanted space for the extra palette so didn't consider smaller designs. If the original ULA fits into something like the EPM240, it would knock a few pounds off the price.

However, about half the cost is in the time taken to build, test, clean and re-test the boards. This still takes a fair bit of time per board even though I've gradually got quicker at the soldering part!

On compatibility, it's possible to put the VideoNuLA in a fully-compatible mode by issuing *VNDISABLE ROM command (or by a simple poke if you don't have the ROM installed). This effectively tells the hardware to ignore writes to the additional registers so it behaves like the original ULA.
Elminster wrote:
Sun Sep 02, 2018 9:57 pm
What I am sort of saying is how hard/cost would it be to produce a VULA replacement as opposed to the endhance version.
It wouldn't be that hard but I'm not sure there'd be enough of a price differential to make it worthwhile. If it's something that enough people are interested in, I'd be happy to look into it in more detail.
Elminster wrote:
Sun Sep 02, 2018 9:57 pm
Not sure if my rambling make sense, made sense in my head.
Makes perfect sense :D

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by dominicbeesley » Mon Sep 03, 2018 9:25 am

As rob says there's a lot goes into making these things. The tone testing, making the manual, developing the code and the tinge consuming process of assembly.

One thing I'd be interested if you've considered, Rob, is the pcb assembly facilities offered by the likes of pcbway. You send them the design and a parts list and they put it together. You can either send them the components or they can source them. I've never built anything production ready but I'm strongly considering it for my next batch of board as they may well involve BGA parts which i don't want to tackle by hand. I've never tried setting up a proper BOM or placement files I'd like to learn more though....

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by Elminster » Mon Sep 03, 2018 9:27 am

Doesnt sound like it is worth doing a cut down version then.

If you wanted 100% compatability at power on, then is the only way to fudge the MOS to poke VideoNula as soon as it can?, i.e. no user intervention.

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by Elminster » Mon Sep 03, 2018 9:31 am

dominicbeesley wrote:
Mon Sep 03, 2018 9:25 am
As rob says there's a lot goes into making these things. The tone testing, making the manual, developing the code and the tinge consuming process of assembly.
I am sure the code is already there, and the manual would be just the fitting bit. It was more whether any saving in the BOM could offset the extra effort, and hassle of mantaining 2 different products. Aware of the issues as I am developing a board for something else (although not nearly as complicated as Videonula as it has no CPLD, just logic).
Last edited by Elminster on Mon Sep 03, 2018 9:32 am, edited 1 time in total.

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by RobC » Mon Sep 03, 2018 10:43 am

dominicbeesley wrote:
Mon Sep 03, 2018 9:25 am
One thing I'd be interested if you've considered, Rob, is the pcb assembly facilities offered by the likes of pcbway.
I did look into it a bit at the outset but decided it wasn't worth it as I wasn't sure how many boards would sell and, partly down to the kind encouragement I got from you and others, I wanted to challenge myself to learn how to solder SMD parts!

I've tended to make them up in small batches to minimise my risk/outlay but, in hindsight, it might have been worth it if I'd got a large batch made up at the start.
Elminster wrote:
Mon Sep 03, 2018 9:27 am
If you wanted 100% compatability at power on, then is the only way to fudge the MOS to poke VideoNula as soon as it can?, i.e. no user intervention.
The simplest thing to do would be to just connect the A1 input/fly-lead to GND. I could produce a nobbled build for the CPLD but it would mean having to reprogram the board if you wanted to go back to full functionality.

To be honest, I've not found any original software that writes to &FE22 or &FE23 when intending to write to the original ULA and so there shouldn't be any compatibility problems. The soft disable mechanism was only added as a "nice to have" just in case something turns up.

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by Elminster » Mon Sep 03, 2018 11:02 am

Useful info thanks.

Of course the otherway to get ULAs is to get everyone to upgrade to videonula and then buy there old working ULAs off them ;-)

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Re: Palettemate / enhanced video ULA with 4096 colours

Post by RobC » Mon Sep 03, 2018 11:08 am

Elminster wrote:
Mon Sep 03, 2018 11:02 am
Of course the otherway to get ULAs is to get everyone to upgrade to videonula and then buy there old working ULAs off them ;-)
Yes - unsurprisingly, I have a few spares :D

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