[Coco] Re: RESET on CoCo 1/2 vs CoCo 3

[Torsten Dittel]

> A lot of software uses this the technique of resetting back to itself as a
> copy-protection tool, to make it harder for someone to break out and
> resave an unprotected copy.  This protection is done by replacing Basic's
> reset vector at $72 with something that points to the program's entry
> point.  The only thing you can do is to find the place in the program that
> does this and knock out that instruction, or the one which stores $55 to
> $71, also required for this technique to work.

Most software was using that to change the artifact color "palette" (red
or blue). It was changing randomly after a reset. I once had a selfmade
Pak (I guess I had that project from the Rainbow or HotCoCo) which was
using the SLENB* cart signal to take over control over the CoCo's
address/data bus and force a "hardware" POKE113,0.

Torsten