Dragon tape pulse frequencies

Hardware Hacking, Programming and Game Solutions/Cheats
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robcfg
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Dragon tape pulse frequencies

Post by robcfg »

Hello everyone!

I'm programming a nice utility for converting wav files to cas files, and I'm wondering what are the frequencies of the 0 and 1 waves.

For the coco, they are 1200hz for 0 and 2400hz for 1, but most dragon tapes are more like 1000hz and 2000hz. Can anyone confirm the right values?

Also, I was wondering if using the PZX format would be a good idea, as it keeps a better representation of the original wave data, and would allow several copy protected games able to be run other than using a wav file.

Cheers,
Rob
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rolfmichelsen
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Re: Dragon tape pulse frequencies

Post by rolfmichelsen »

Hmmm... Inside the Dragon claims the same frequencies, 1200 Hz for a 0 and 2400 Hz for a 1. I guess this isn't really that accurate, but the difference between the two frequencies is so significant that detection is possible anyway. If I recall correctly, each bit is encoded as a full waveform of the given frequency, so just detecting the time between 0 crossings should be sufficient.

-- Rolf
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robcfg
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Re: Dragon tape pulse frequencies

Post by robcfg »

Ok, thanks!
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