But iam not shure what is behind that´s Option/Projekt ?
« “ROR” in Microsoft BASIC for 6502Transactor November 1987: Volume 8, Issue 3 (PDF) »Create your own Version of Microsoft BASIC for 6502
If you disassemble a single binary, you can never tell why something was done in a certain way. If you have eight different versions, you can tell a lot. This episode of “Computer Archeology” is about reverse engineering eight different versions of Microsoft BASIC 6502 (Commodore, AppleSoft etc.), reconstructing the family tree, and understanding when bugs were fixed and when new bugs, features and easter eggs were introduced.
This article also presents a set of assembly source files that can be made to compile into a byte exact copy of seven different versions of Microsoft BASIC, and lets you even create your own version.
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Source: http://www.pagetable.com/?p=46
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