How Do Tape Accelerators Work?

Post by **Jeff-20** » Wed Jun 30, 2004 12:55 am

I remember seeing plenty of ads for carts and programs to accelerate the tape drive for the Vic. How do they work? I don't get it.

Zeela · Post by **Zeela** » Wed Jun 30, 2004 2:32 am

I'd say that they work something like the Turbo Tape programs for the C64...

I'm not an techie-expert on this but...

They all play around with the signal to the taperecorder. Using "shorter" signals for 1 and 0 than the original. Then they alter some of code in reading from tape and process the signals to handle this.

Well, someone else must have a better explanation, but this I think is the concept behind it.

// Zee

Schema · Post by **Schema** » Wed Jun 30, 2004 9:54 am

Also, I read somewhere that the VIC normally saves each program on tape twice for error checking. The tape speeders skip this second step, thus halving the load time!

Boray · Post by **Boray** » Wed Jun 30, 2004 10:53 am

The 64-turbos are 7 times faster, so I think the original tape routines saves everything 8 times just to be safe...

/Anders

Mikam73 · Post by **Mikam73** » Wed Jun 30, 2004 3:05 pm

Does some orginal Vic20 tape games have turbo load system?

Like C64 tapes..

carlsson · Post by **carlsson** » Sun Jul 04, 2004 8:06 am

I believe Turbo Tape 64 was invented in 1983, and other turbo loaders (Jeff Minter/Llamasoft used one, Ian Gray/Interceptor Micros used another) were of the same date. The VIC still was around in 1983, but maybe starting to fade a little. Also, even expanded VIC games load within 16K or less, so the loading times of half an hour were not as important to cure as on a bigger machine.

Boray · Post by **Boray** » Sun Jul 04, 2004 8:33 am

Half an hour? Doesn't 16k load in about 5-6 minutes without turbo? Or maybe that was your point?

/Anders

carlsson · Post by **carlsson** » Sun Jul 04, 2004 12:39 pm

Yep, I tried to refer to even larger (C64) programs.

Post by **Jeff-20** » Sun Jul 04, 2004 4:24 pm

I was shocked when I first loaded a really long C64 program from disk. I couldn't believe how long it took to load a full memory program to the 64... the most memorable was Test Drive.

Mikam73 · Post by **Mikam73** » Sun Jul 04, 2004 5:43 pm

Copy of C64 Ghostbusters did load 15min from tape..

Mayhem · Post by **Mayhem** » Mon Jul 05, 2004 4:02 am

I don't know what release you had then, it only took 3 minutes here in the UK...

Mikam73 · Post by **Mikam73** » Mon Jul 05, 2004 4:10 am

Mayhem wrote:I don't know what release you had then, it only took 3 minutes here in the UK...

It was copy, not orginal version. And we did transfer file from disc to tape.
One big file. I have same version on my Ide64.. Now it loads about 1s.

carlsson · Post by **carlsson** » Mon Jul 05, 2004 4:25 am

Sounds like you had a 250 block memory dump (from freezer cartridge etc) to load. The largest C64 file I have (cracked version of Mayhem in Monsterland) takes something over 300 blocks and thus loads in sections using a custom loader.

Mikam73 · Post by **Mikam73** » Mon Jul 05, 2004 5:29 am

Yes.. There is screen full of those flashing color bars before game starts after loading. Game loads fast from Ide64.. but it takes some time before game starts.. Ghostbusters!