[Coco] Old Copy Protection Schemes

[Arthur Flexser]

I've only heard of self-destructive copy protection in connection with
"Mr. Dig", a game from Computerware.  When it thought it detected an
illegitimate copy, it wrote "BUY YOUR OWN" all over the directory and/or GAT
sectors of the disk.  (Due to a bug, it ruined some unknown number of legitimate
copies, when the user was hapless enough to try to boot the game from a drive
numbered other than zero.)  Generally, illegitimate copies are detected by
checking the contents of the track's header information.

Art

On Fri, 9 Sep 2005, Steve Ostrom wrote:

> Included in a recent eBay purchase of some Coco equipment was someone's 
> backup disk containing three programs, including Blackbeard's Island, a 
> graphic adventure marketed by Tom Mix and written by Greg Miller.  I 
> made a copy of this disk, then ran Blackbeard's Island from the copy.  
> There was an entertaining graphical intro of scrolling words on an old 
> fashioned scroll, then the program quit at the same time as the floppy 
> drive started and quickly stopped.
> 
>  I rebooted my Coco3 and checked the directory of the diskette and found 
> the other two programs were still there but Blackbeard's Island was now 
> gone.  This is the first time I have run into a self-destructing copy 
> protection scheme.  I can't imagine this was common, but I think I 
> remember Marty being very agitated about this type of copy protection 
> especially.  Was this one of the only programs to utilize one of these 
> "Mission Impossible" self-destructs?  Are there any details on how the 
> program knows it is a copy?
> 
> -- Steve --
> 
> 
> 
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