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[HP 71B] JPC ROM F05 - Printable Version

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[HP 71B] JPC ROM F05 - J-F Garnier - 03-13-2017 08:27 AM

(02-02-2017 07:57 AM)J-F Garnier Wrote:  
(02-01-2017 10:22 PM)dayd Wrote:  During development, I came across what might be a big bug in the JPC ROM (F04) in the RED$ function. With an empty string, at runtime the function through an error ‘String Overflow’. If you type directly RED$("") it freezes the computer and then INIT:1 does a CLAIM PORT on all the IRAMs at once, erasing all content of course!

You found a new bug in the JPC ROM ! Amazing that it remained unknown for such long time.

(02-02-2017 05:15 PM)J-F Garnier Wrote:  Regarding the (real) RED$ bug, it was introduced in the JPC ROM X (or Ex), and is present in all versions F.
Also the bug happens with RED$(" "), CENTER$(""), CENTER$(" ").
RED$ and CENTER$ work fine in JPC ROM D (and previous versions), as well as in the original DESAL Lex.

The RED$/CENTER$ bug is now fixed in the JPC ROM revision F05.

Thanks to Christoph Giesselink for documenting the code involved in the bug and proposing the fix.