There are two ways to get VIC-20 software for use with Power20. You can visit one of the VIC-20 archives on the Internet or copy it from your old collection of 5.25" disks.
Please be aware of the copyright problems attached to VIC-20 games. The fact that the VIC-20 is no longer produced, and hardly any new software is available for it, does not mean that the old commercial software has in general become public domain. Even old software, that is no longer sold, is still intellectual property of its author and protected by copyright laws. Only few authors (such as the great Jeff Minter) have actively decided to release their (once commercial) work into public domain. All others have, up to now, just chosen not to take any action against copyright infringements (but may of course revoke this decision at any time).
In other words, the collection mentioned below consists primarily of pirated software. Use it at your own risk - You have been warned!
A detailed study on emulators and the problems that they pose in relation to Intellectual Property Rights can be found at http://emulegal.emuunlim.com
If you are looking for VIC-20 software on the internet, you might want to look at the following sites:
Here are some hints, that will seem trivial to experienced internet users and are meant to help newbies avoid the most frequent errors.
VIC-20 games are always stored in binary, never in text (ASCII) files. If you are using a FTP program for downloading make sure it is switched to binary mode. If you are using a webbrowser such as Safari, Firefox, iCab or Opera press the option key when clicking on the link of a game. Otherwise there is a good chance that you will end up with a file that looks fine at first glance but is internally corrupted and unusable.
Most games for the VIC-20 are stored as plain *.PRG files without any compression, as the files tend to be very small (a few KByte) and compression does not really pay off for such tiny files. They can be used without any additional preparation.
On the other hand, you might find some compressed files on the net. Some sites offer games in a compressed format, that saves disk space and network bandwidth. Common file extensions for compressed files are: ZIP, GZ, LHA and SIT. Power20 can use ZIP, GZ and LHA files directly - there is no need to waste hard disk space by decompressing them before use. SIT files need to be expanded before they can be used with Power20.
The easiest way to expand a compressed file is to drag and drop it on StuffIt Expander with Expansion Enhancer. Both StuffIt Expander and Dropstuff with Expansion Enhancers are available at your local info-mac archive or from Smith Micro Software at http://my.smithmicro.com/mac/stuffitexpander/index.html.
StuffIt Expander is freeware, Dropstuff with Expansion Enhancer is shareware and together they expand all the important file formats.
Some sites also offer SFX files. These are Self Extracting LHArchives, that need to be unpacked on an (emulated) C64 (such as Power64 by Roland Lieger) or C128 but unfortunately not a VIC-20. The easiest way to do this probably is to mount the folder containing the SFX file as drive #9 and place a new disk image (or a disk image with sufficient free space) in drive #8. Now LOAD and RUN the SFX file, just like any other C64 program. It will ask for a drive and a device number. Answer '0' and '8' respectively and stand by as the archive is unpacked onto the floppy. When expansion is completed, you have the playable game on the disk, that can now be used like any other D64 file. The SFX file is then no longer needed.
Note that the C64 is a slow computer (in comparison to your Mac). Decompression might take quite a while. If you are using Power64 then you might want to increase the CPU speed using Options/Turbo Boost.
If the expansion tool complained about a bad file structure, checksum errors or similar problems, the most likely cause is that you made an error in downloading. Remember: All VIC-20 games (compressed or not) are stored in binary files! When in doubt use an specialized FTP tool for downloading. Don't (ab-)use your webbrowser for FTP sessions.
Now you hopefully successfully managed to expand the downloaded games. Still the files look dull on your Macintosh desktop and double-clicking on them does not start Power20. Please remember that there are computer systems other than the Macintosh out there. They have no idea of the Type/Creator system that the MacOS uses to keep files linked to icons and applications. Thus such information is not stored in the compressed file and can therefore not be retrieved when it is expanded.
Still Power20 is able to use such files, if you manually start Power20 and use the Device menu to attach a D64, T64 etc. to an appropriate drive. If a file does not have one of the characteristic extensions, it is most likely a CBM program file and you should mount its folder as a hard disk. After a file has been successfully loaded Power20 will adjust the Type/Creator for this file, so that it can be opened Mac style by double-clicking.
You can find many links to interesting VIC-20 sites on the Power20 homepage:
If you do not want to search for games yourself there are also internet search engines specialized on the Commodore Software (mostly C64 stuff):
There is another VIC-20 Emulator for the Macintosh. Unfortunately the current version 0.6 is far from perfect. The emulation is slow and imprecise. Many games do not work. Still you might want to look at Matthew Browne's VIC 20 Emulator at:
Project64 attempts to conserve Commodore related documentation as ASCII Texts. While there is little material that is specific to the VIC-20, a lot of the C64 material also applies to the VIC-20:
While Project64 collects only english documentation, the international CBM documentation project iDoc provides etexts in many languages (incl. English, German, Swedish, Hungarian...).
More Commodore related wisdom is accumulated at the Commodore Knowledge Base:
There are also several VIC-20 emulators for various other systems. While you will not be able to use them on your Mac, they still offer a lot of information and links around the VIC-20:
An excellent overview of emulators (for all kinds of machines) on the Mac can be found at:
There are also newsgroups that are devoted to Commodore computers (news://comp.sys.cbm) and their emulation (news://comp.emulators.cbm).
If you have your own collection of documents and games that you wrote yourself, and that are not publicly available you can copy these from 5.25" disk to your Mac. Unfortunately this is not a straight forward job. Still there are several options:
If you have a collection of private files on (audio) cassette tapes, you can attempt to convert them for use on your Mac. This is however a rather tricky process, that starts out by converting the tapes to uncompressed WAV files (do NOT attempt to convert them to MP3 (or similar compressed formats) since the compression scemes are optimised for the human ear (and not for computer 'listeners') and will discard information that is essential for data recovery). These files can than be converted to TAP and/or T64 using a Windows PC (unfortunatly not a Mac) and one of the following tools:
A good collection on hints for the conversion of tapes to TAPs or T64 file images, can be found at the Commodore 64 Tape Transfer FAQ.
Power20 Homepage: http://www.infinite-loop.at and http://www.salto.at - EMail:
© Roland Lieger, Goethegasse 39, A-2340 Mödling, Austria - Europe
Last Changed: Feb. 29, 2008