Thread: Dragon 32
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Old 7th Oct 2019, 6:03 pm   #4
Electronpusher0
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Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 2,288
Default Re: Dragon 32

Many years ago I worked for ATE systems in Chichester (now defunct) and we were developing a cable harness tester for testing such things as Aircraft looms.
We based the computer control on the same Motorola applications note as the Dragon. We used Dragon 64s (same as the 32 but twice the memory) as test beds to develop the software.
The Dragon used a 6809 8/16 bit processor.
I spent some time de-compiling the code of the Dragon out of curiosity. It used a technique that we regarded as bad practice at that time - self modifying code.
Part of the code was held in Ram, loaded at boot. First time through that bit of code it did one thing, the code was then modified and subsequent passes through that bit of code did something completely different.

Peter
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