VIC-20 Multicart

[Schema]

Any options/ideas of configurations for that Super Game Expander we discussed at WOC and Leif volunteering to do the menu for such?

From a hardware point of view, I know exactly what to do to. However, apart from KilrPilr and, perhaps you, nobody seems interested in buying such a cart.

To make it worthwhile, a multicart for the VIC would have to be produced in at least 50 units and I really doubt I could ever sell half a dozen of them...

I think this topic deserves its own thread!

I am definitely interested in a multicart for the VIC. With a kid and other distractions, the convenience of loading and running a game quickly is important to me. Also, the reduced wear and tear on old VICs from not having to insert/remove cartridges is appealing.

eslapion, can you tell us more about the hardware? My questions are:

-How many games could it hold?
-Will it be possible to change or update the games?
-Is it only cartridge ROMs, or disk/tape games as well?

Everyone else - speak up if you want one!

[Mikam73]

Everyone else - speak up if you want one!

Yes. It would be great to have one or two..

Rather to have one that had all Vic20 cartridges at one cart.

[vic user]

i am interested too

[Centallica]

Is it possible instead of having a 5 cart expander a "5 ROM expander" where we could select a ROM with games on it from 5 different ROMS? Toggle switches or something? Or would we go the flash card route?

I would be interested just the selection of games I would have to determine.

Maybe a Pre-order deposit to show faith of intent to buy like $25 might separate the talkers from the buyers too.

Brian

[Mikam73]

http://www.atarimax.com/usbcoleco/documentation/

Something like this would be great..

[orion70]

I am definitely interested in a multicart for the VIC. With a kid and other distractions, the convenience of loading and running a game quickly is important to me. Also, the reduced wear and tear on old VICs from not having to insert/remove cartridges is appealing.

How about loading cart ROMs from disk with your 32K RAM expander permanently in? It's as easy as typing load"game",8,1 and reset the VIC

[Centallica]

http://www.atarimax.com/usbcoleco/documentation/

Something like this would be great..

The price is a bit scary though

Brian

[Mikam73]

http://www.atarimax.com/usbcoleco/documentation/

Something like this would be great..

The price is a bit scary though

Brian

Well.. Maybe a little.. But you can load 127 Coleco roms to it and its very easy to use. If there was something like that for Vic, you wouldnt need carry so many cartridges with you to computer party.

(And I rather leave rare ones home anyway)

[eslapion]

eslapion, can you tell us more about the hardware? My questions are:

-How many games could it hold?
-Will it be possible to change or update the games?
-Is it only cartridge ROMs, or disk/tape games as well?

How many games:
The original theory for the multicart is based on having a 74LS373 octal latch controlled via the I/O2 or I/O3 chip select line tied to the data bus of the cartridge port. The output of the logic chip can then be used to control the higher address lines of a large capacity Flash ROM or EPROM or OTP PROM chip.

By poking a number ranging from 0 to 255 to any byte in that memory range, you could select a cell from the large chip. Since cell 0 will contain the menu software that allows you to choose which game you want to play then you have a theoretical maximum of 255 games.

Will it be possible to change or update the game:
That depends completely on the type of memory chip being used. I don't recommend using flash memory because you don't want your multicart to start losing its content after 10 years. Personnally, I would prefer to have an OTP chip because it is the only type of memory that has no lifespan limit. The MTBF of an OTP is "expected" to be around 150 years.

Just in case somebody has the bright idea of mentioning electrically erasable EPROMs (EEPROMs), a 4Mbit chip is 700$.

Is it only cartridge ROMs, or disk/tape games as well:
Unless somebody converts them to cart format, disk/tape games are not supported.

In reality supporting 255 x 16k games would require a 32Mbit chip and this does not exist in the parallel format required by the VIC.

The real limit is more like 64 cells of 16k (63 games + 1 menu) or 128 cells of 8k (127 games + 1 menu) using the largest chip I have found, 8Mbit. An OTP chip of that capacity is around 7$. A UV erasable is 9$.

I think the cost of such a multicart would only be around 40$. However, the real job is to create the .bin file containing all the games' ROM images to program the ROM chip.

[ruud]

I am definitely interested in a multicart for the VIC. ....

Some years ago Marko Makela was working on a cartridge with just a minimum of hardware for registers and a 29F040. I sent him an email to ask him what happened to this project.

I'm willing to think about this and dream up a schematic as well. But there is only one small problem. I have a game called 'Spiders on Mars' and I know that it has more the 8 KB of ROM. So this rules out assuming that all games can be found at $A000. The information I need is:
- what game is situated at what address/block(s)
- is extra RAM needed.

My vague idea:
- 32 KB of SRAM (if needed)
- a 29F040 FRAM
- a 6522 for having some register I/O
- some glue, if possible standard TTL, otherwise GAL, in the worst case CPLD
- The FRAM can be filled by the VIC-20

[Mikam73]

I asked about it last summer when I saw him. It is slow going freetime project that might come ready sometimes in future. I ask about it after couple years again.

But old copyrights can always be problem, it might be illegal sell multicart for Vic20. I remember very well when Funet frp had to remove Vic20 roms after some search bot at internet sent email that there is copyright softwares at their ftp.

I guess thats why AtariMax sells their carts empty.

I am definitely interested in a multicart for the VIC. ....

Some years ago Marko Makela was working on a cartridge with just a minimum of hardware for registers and a 29F040. I sent him an email to ask him what happened to this project.

[carlsson]

I think the main reason why Marko took the VIC-20 archive offline and later transferred the whole cbm directory to Bo Zimmerman was that Funet is state financed (?) and run on the university network. A possible lawsuit about copyright breech would not only look bad, but be fatal to him as being responsible for it. A private-owned ftp is a smaller business. Actually, the bot only looked for keywords and had marked down a few titles, but it was just as well to take everything offline.

With Atari, there is clearly a new owner of the brand who claims to also hold copyrights of the old games. Whether they're legit or not, someone yet has to prove in a lawsuit. The new owners of Commodore would be Yeahronimo, and yet they don't make a lot of noise. Of course many cartridges were made by 3rd party companies, of which a few still exist or at least another company is known to have the rights (I'm mainly thinking Atarisoft and Epyx, but probably others as well). It is a grey zone to sell a multicart loaded with ROM images. A flashable device, perhaps a smart card MMC device which can be loaded with any files you wish, would not only be more safe legally wise, but tend to more owners. I don't have a particular interest in a 32K memory expansion - I have a lot of those already - and I'm not interested in a multicart, but I could be interested in a smart card based cartridge, even if it is VIC-20 only.

[Mikam73]

I think that it would be nice if there was device like MMC64 with memory expansion for Vic20. If somehow it would be possible load ROM images and PRGs there.

Those devices are like todays MP3 players, you dont have to carry loads of CDs with you..

[ral-clan]

$40 for a multicart and I'm in! Especially if the memory is Readable/Writeable.

[Schema]

The real limit is more like 64 cells of 16k (63 games + 1 menu) or 128 cells of 8k (127 games + 1 menu) using the largest chip I have found, 8Mbit. An OTP chip of that capacity is around 7$. A UV erasable is 9$.

I think the cost of such a multicart would only be around 40$. However, the real job is to create the .bin file containing all the games' ROM images to program the ROM chip.

Would it be possible to independently select which 8K cells are assigned to Block 3 and Block 5?

That way, you may be able to mix 8K and 16K games and get higher capacity.

Using what I believe is the latest list, there are 183 game carts listed.
http://www.digitpress.com/the_digs/vic2 ... c-rare.htm

Total size of all ROMs listed is 1558K. However, 29 of them are 4K games which would still require an 8K cell (wasting 4K).

This brings us to 1704K, and surely this would fit in a 4M chip easily, or is there something I have misunderstood?


As for mixing 8K and 16K games, here's what I suggest, assuming we can select Block 3 and Block 5 cells individually.

Each game in the menu would have two bytes associated with it, one to indicate which cell goes in Block 3, and a second to indicate which cell goes in Block 5.

For 8K games, they could just point to the same cell (Block 3 not used, except for Scott Adams games). For 16K games, they would point to the top and bottom "halves" of the game.

Would that work?