Spectrum Computing

Hi All,

A Simple, yet, probably stupid question, but, is there a way to fast load from a tape into a +2? I realise that the screeching sounds you hear when loading from a tape are essentially the 0s and 1s being chucked into memory (or something like that) so could the humble Speccy cope if these screeching sounds were from a sped up tape?

I’m not sure I understand your question. Being somewhat of a (self-proclaimed) expert on tape loaders, I can tell you that the Spectrum can easily cope with data rates that are six to maybe ten times the standard ROM loader. However, that would require a high-quality audio source and a specially written loader.

Here’s the gist of how tape loading works. The tape contains an audio signal that alternates from a low to a high level at different frequencies. Each time a signal level crosses a certain threshold from low to high or from high to low (in most Speccy loaders, including the ROM loader, it doesn’t really matter which way it goes), a counter starts. When the signal changes from high to low (or low to high) again, the counters stops and the code then looks at how many times the counter has counted. If it’s below a certain value (i.e. a shorter period), then the loader writes it down as a zero; if it’s above that value (a longer period), then it’s considered a one; and if it’s longer still, the loader gives you an error.

So, tape loaders are fairly speed dependent. The lower a loader’s rate, the less sensitive it is to speed variations. You can get away with a great deal of wow and flutter and still load tapes with the standard ROM loader. As the data rate increases, loaders typically become more susceptible to changes in speed.

Another factor is the frequency of a signal. The Spectrum can deal with very high frequencies. Many tapes—and many tape recorders—are not capable of reproducing them, however.

So, to answer your question, no, for the most part, you can’t just load any program by running the tape at twice the standard speed. However, a custom loader can do that, and most were written just for that purpose.

Make sense?

Yep, that makes sense. I just wondered if it was possible. You know, just one of those ‘I wonder if....?’ moments.

I’m collecting more and more tapes and as fun as it is it’s still a ball ache waiting for them to load.

Also, since the VHS format has a better audio quality than the standard audio cassette, you can use it as a high speed medium

https://www.youtube.com/watch?v=nfJvYLkocUQ

Gonna be a bit of a ball ache to copy my tapes to a VHS tape