If you are using a 1541 or 1541-II diskdrive with your Vic20, you can use the following command:
OPEN 15,8,15,"UI-":CLOSE15
It will make the drive go about 20% faster (=turn it into a 1540 drive). The 1541 drive is slower because the C64 is slower. You have to use the command after every reset if you want to drive at Vic20 speed.
/Anders
1541 tip
Contrary to popular belief, you don't have to issue the command to use the drive with the VIC - it is quite common to see this misunderstanding even among seasoned Commodore users and serious information resources.
I measured once, and got about 15% speed increase compared to the 25% the manual claims, but the larger the file, the more the difference will be. In particular if the files are stored on the disk in some clever order (i.e. from track 1 to 35 rather than the default Commodore DOS working from the inside, track 18, and out in both directions), you should get some really good results.
Hmm.. is there any real disk turbo for the VIC-20? I should know, but I keep forgetting. There is a track loader used in the demos, but I don't know if it has some speedup or if the VIA circuits can be programmed for this.
I measured once, and got about 15% speed increase compared to the 25% the manual claims, but the larger the file, the more the difference will be. In particular if the files are stored on the disk in some clever order (i.e. from track 1 to 35 rather than the default Commodore DOS working from the inside, track 18, and out in both directions), you should get some really good results.
Hmm.. is there any real disk turbo for the VIC-20? I should know, but I keep forgetting. There is a track loader used in the demos, but I don't know if it has some speedup or if the VIA circuits can be programmed for this.
Anders Carlsson
