[Coco] tape format

[Roger Taylor]

Could the CoCo have had a more reliable tape format?

Read this page:

http://en.wikipedia.org/wiki/Kansas_City_standard

I think the CoCo could have had a more reliable format (perhaps) if a 
1500hz/3000/hz system was used, or maybe even 2400hz/4800hz, either 
format, but outputting 2 cycles of the faster wave.  The standard 
CoCo format outputs 1 cycle of both waves, causing a wobbly format 
that's bot easy to get out of sync, and easy to misread the faster 
cycle on cheap media.

If 2 cycles were used you'd get a more reliable load, I think.   The 
time length for a 1-bit would be the same for a 0-bit.  This could 
give a faster format even before the 2mhz POKE.  I think a 4000 baud 
format isn't impossible.

Back in the BBS days I experimented with using a VCR's audio line to 
record 2mhz cassette saves, and it worked.  What I did was save VDG 
screens in a series using CSAVEM and then the loader read them back 
from the VCR tape pretty fast.  This was mainly just to see how fast 
the loads were and if there were no errors, etc.

The regular audio tape decks couldn't handle the 2mhz saves/loads for 
some reason.  I don't know if it's the save or the load that goes 
wrong, but it's not the CoCo itself.  Again, I confirmed this using 
digital devices such as an MD Walkman and a recent Audio Voice 
Recorder ($39 at Wal-Mart).  That thing records through Line In, 
saves as MP3 and has a USB cable for your PC.  Using that little 
device you could move CoCo cassettes to the PC, I'm sure.  Never tried.




-- 
Roger Taylor

http://www.wordofthedayonline.com