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joeypsp

playing roms on a commodor Vic-20?

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okay, so i may be getting a Vic-20 in a few days, and its gonna have a tape drive, and floppy drive.

 

so the question is, is it possible to play downloaded roms on a vic 20 if i put them on a floppy disk? its got some games with it, but, being so old, it could be a bit troublesome to track down some games in the wild.

 

sorry if this isnt allowed, i just figured since you host atari backups and such, alwell the fact that theres no profits to be had off most of those games nowadays.

 

Also, does anyone know of some good games i should look into, any genre will do.

 

im also gonna try my hand at programming on it, with its wopping 5 kilobytes of ram lol :D

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It depends on what you mean by 'roms'.

 

If it's a disk image, you will need a way to create the disk for your Vic 20. You'll need an X1541 type cable for your computer or you can use a C64 to make the disk image for you. I use an MMC64 to make all images for my C64s/128s/Plus4/16/116/Vic/etc

 

If it's a ROM you should be able to SYS to the starting address and run it once it's on a tape or disk.

 

Besides the Mega Cart, you can also try http://www.8bitcentral.com/behrbonz.htm . It's a bunch of carts on a cartridge also and works pretty well (I have one).

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Megacart gives you all the memory expansions you'll need, every dumped cartridge game found, a selection of impressive commercial and homebrew games from the last 30 years and a bundle of utilities. Well worth the money. To transfer other stuff as noted above though, you'll need a cable to connect the disk drive to the PC and use some software to copy the files over, or something like the MMC.

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Mayhem is spot on... if you're interested in doing any VIC 20 programming, you should browse over to the Denial forum -- a very active VIC 20 community in terms of playing and developing -- all your newbie questions will be answered. Personally, I got one of these cable adapters for my PC parallel port to hook-up the floppy drive -- cheapest way to transfer binaries between PC and a real VIC. Later on, got the uIEC/SD which was the fastest and most convenient way without fussing with the 1980s media.

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The short answer is yes.

 

You can download pretty much every game ever released for the VIC20 including ROM games and play them on a real VIC.

 

You will need to overcome two problems:

 

1. How to get the downloaded games onto a media the VIC can read.

 

2. How to install physical RAM into the banks needed by the downloaded game.

 

 

The first issue is most easily solved by using a uIEC device from Jim Brain. It costs $55 plus shipping and allows you to take SD cards from your PC to the VIC.

The uIEC allows entire disk images in .D64 and .D81 format as well as individual PRG files to be easily loaded.

 

http://www.jbrain.net/products/uIEC%7B47%7DSD.html

 

If you don't want to do that, you can buy or make your own X1541 cable that allows you to connect the 1541 disk drive directly to a PC's parallel port.

Software such as Star Commander can then be used to writes directly to the Commodore disk. I used this technique for a long time, but found that Star Commander does not work under Windows and is highly temperamental. Downloading files from the internet, copying them to PC floppy to be transferred to an ancient laptop running DOS 6.2 and then hooking my home brew 1541 cable to the Commodore disk drive gets really really tedious.

 

The VIC disk subsystem does not require any machine memory but as such uses an utterly bizarre syntax to interface with the disk drive. The disk system is also unbelievably slow.

 

 

 

The second problem concerns the VIC's memory map. The VIC memory map is divided into eight 8K banks numbered 0 through 7. The standard machine shipped with bank 0 partially populated - 5K. This leaves a 3K hole in bank 0. RAM memory could also be placed in banks 1, 2 and 3. Bank 5 was used for ROM cartridges and so RAM will need to be present here if you wish to load ROM games from disk or tape.

 

Many great games will play on the standard 5K but some require the 3K hole to be filled using a 3K memory expansion unit. Memory can also be placed in banks 1, 2 and 3 using 8K, 16K and the rare 3rd party 24K memory expansion units. The best VIC20 games typically require a 16K expansion unit. There are a few games that require a 24K expansion.

 

Oddly perhaps, the BASIC interpreter will not recognize the 3K expansion if memory is present in bank 1. The 8K and 16K cards do not back-fill the 3K hole so games that require the 3K expansion will often not run on a 8K or 16K expanded machine. Some memory expansion cards offered a switch to move between 3K expansion and 16K expansion. These are now quite hard to find.

 

All ROM games used memory in bank 5. Larger ROM games used a second bank - usually bank 3.

 

This presents a problem as the standard Commodore 8K and 16K memory expansion cards only fill banks 1 and 2. To place memory in banks 3 and 5 you will either need to open the 16K memory card and change the jumpers to relocate the memory banks. Alternatively some third-party expansion adapters allowed multiple RAM expansion cards to be inserted and dip switches could be used to change the location of the extra RAM. The Stonechip 4-slot expansion card offered this feature, but is rarely seen on Ebay.

 

Some third-party RAM expansion cards also offered dip-switch solutions to allow the user to dictate which banks would be filled, such as the Cardco expansion unit. Again these are quite rare.

 

To further complicate matters, some ROM dumps including Atarisoft Pole Position and Battlezone require a soft reset to initialize the game. There are instructions on the web that show how to wire a simple switch to the Reset line of the cartridge port, but it will require some soldering to implement.

 

By far the simplest solution to the memory question is the MegaCart which besides including almost every VIC20 ROM game, also features a full 32K + 3K memory expansion option allowing you to place memory in all banks. The implementation of Pole Position and Battlezone on the Megacart force a soft-reset by-passing the need for a user-installed soft-reset.

 

 

 

If you can work your way through the quirky disk system and the quirky memory map, you can enjoy some classic retro gaming including:

 

A.E.

Arcadia

Avenger

Bandits

Bongo

Capture the Flag

Country Garden

Hellgate (PAL systems only)

Jelly Monsters (best home Pacman conversion of any 8-bit system. Period.)

Jetpac

Jupiter Lander

Lazer Zone

Matrix

Omega Race

The Perils of Willy

Trader

Victoria

 

I hope you have fun.

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right on, thanks for all the info dudes :thumbsup:

 

i was looking at a mega cart, and all though it seems like it would be an end all decision and play everything, its like $100, im gonna check out oracle_jedi's methods, who i must extend a great thanks to, you put alot of time into writing all that so im not gonna let it go to waste, thanks for all the info man, im gonna go for the uIEC/SD i think :thumbsup:

 

or is the mega-cart REALLY worth it? :?

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or is the mega-cart REALLY worth it? :?

 

The Mega-Cart is truly worth every penny and more. Just for playing ALL of the abandoned game ROM cartridges alone is worth its price (you can't collect them all for under $100). There is also a healthy list of the best homebrew games, instead of downloading and transferring to old media and learning how to LOAD them into memory, etc. Then there is the built-in RAM memory for all memory expansion configurations (which gets automatically used when you select a game title requiring more RAM). And there is NvRAM in it that saves some game's high scores, too, one in particular that comes to my mind is Quikman+ ;)

 

...and there is still more stuff on the Mega-Cart besides the typical entertainment value listed. Like I said, worth every penny.

 

I have high regards for a uIEC, too, but IMO, it is not worth owning just for a VIC, because Mega-Cart would be enough. I have all the C= home computers, and the uIEC works for all of them too (not PETs). If you have more than one C= computer, this drive is definitely worth owning.

 

Good luck and have fun!!

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Oddly perhaps, the BASIC interpreter will not recognize the 3K expansion if memory is present in bank 1. The 8K and 16K cards do not back-fill the 3K hole so games that require the 3K expansion will often not run on a 8K or 16K expanded machine. Some memory expansion cards offered a switch to move between 3K expansion and 16K expansion. These are now quite hard to find.

The VIC (video chip) sees memory differently than the CPU. Jim Butterfield did a series about it that you may find interesting:

 

Visiting The VIC-20 Video, Part 1

Part 2

Part 3

Part 4

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Oddly perhaps, the BASIC interpreter will not recognize the 3K expansion if memory is present in bank 1. The 8K and 16K cards do not back-fill the 3K hole so games that require the 3K expansion will often not run on a 8K or 16K expanded machine. Some memory expansion cards offered a switch to move between 3K expansion and 16K expansion. These are now quite hard to find.

The VIC (video chip) sees memory differently than the CPU. Jim Butterfield did a series about it that you may find interesting:

 

Visiting The VIC-20 Video, Part 1

Part 2

Part 3

Part 4

 

SpiceWare: Thanks for pointing to the interesting article.

 

As far as the MegaCart is concerned, if you're at all interested in 8-bit retrogaming and the Vic, get it now (while you can). I put it in the "dream category" of totally feature-packed be-all-end-all products. (1541 Ultimate for C64 and USB SIO2PC for Atari in there as well)

 

The Vic is now a cherished part of my collection, and I would have never have experienced the Vic in totality without MegaCart.

 

All I wish for now is S-video from the ol' Vic. (currently use an Atari 8-bit composite monitor cable and works well)

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SpiceWare: Thanks for pointing to the interesting article.

No problem - I probably should have pointed out the specific bit from part 1 for oracle_jedi

 

Looking at the diagram, we can begin to see why the VIC does its odd screen switch when you add memory. In the 5K VIC, the screen sits at the top of memory – and that's the highest address that the video chip can see (block 15.5). If we add 3K RAM expansion, the screen can stay where it is above the BASIC RAM area. But if we add 8K or more, the video chip can't see that high, and the screen memory must flip down to the bottom where it won't get in the way of your BASIC program. Which bottom, you may ask? It turns out to be block 12, which is memory address 4096 or hexadecimal 1000, even if the 3K expansion is in place.

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Later on, got the uIEC/SD which was the fastest and most convenient way without fussing with the 1980s media.

 

 

The first issue is most easily solved by using a uIEC device from Jim Brain. It costs $55 plus shipping and allows you to take SD cards from your PC to the VIC.The uIEC allows entire disk images in .D64 and .D81 format as well as individual PRG files to be easily loaded.

http://www.jbrain.net/products/uIEC%7B47%7DSD.html

Thanks for the pointer, mine arrived last night!

 

I'd previously picked up an MMC64 + RRnet (ethernet daughterboard), and while it works fine it doesn't support my C= 128 in 128 mode nor my VIC 20.

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