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4K HP 67 Games rom attached for testing
10-30-2016, 03:52 PM (This post was last modified: 10-30-2016 08:45 PM by Dieter.)
Post: #31
RE: 4K HP 67 Games rom attached for testing
(10-30-2016 02:11 AM)Gene Wrote:  I wonder if my use of flag 2 rather than 22 has messed this up for number entry (possibly) or something else I have not quite done right.

I haven't checked your listing but the 67/97's data entry flag 3 is equivalent with the 41's flag 22. So SF 3, CF 3 and F? 3 become SF 22, CF 22 and FS?C 22.

BTW, this sequence...
171 RCL 23 
172 FS? 02 
173 10 
174 FC?C 02 
175 0 
176 + 
177 STO 23

...will not work either. This adds 10 or 0. The original program adds EEX 0 = 1 (!) if flag 2 is set (or 0 otherwise). On the 41 you could do it this way:

171 RCL 23 
172 1
173 FC?C 02 
174 CLX 
175 +
176 STO 23 

- or with one stack level less -

171 RCL 23 
172 FS?C 02 
173 ISG X
174 LBL 09
175 STO 23

And there are more errors. For instance steps 047...050 are duplicating the ones before and have to be removed, or a GTO B turned into GTO b.


(10-30-2016 02:11 AM)Gene Wrote:  I don't understand the last two steps either.

Maybe I got the idea behind this. The (second) label B at line 217 of the original program seems to be the common endpoint where the result is displayed. The instructions say that here a [R/S] will re-enter a value calculated by a function that was not part of the program, e.g. sqrt or log. This [R/S] will then set flag 3 and quit (c.f. the last two instructions) so that subsequent operations accept the result as a new entry.

I now have a corrected version for the '41 but it still does not work quite right. So there's still something left to do. And I'm sure the 41 version can get shorter than the original as storage arithmetics is available for R23 and R24, and because not just R25 can be used for indirect addressing.

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HP-67 AOS program to debug - Gene - 10-30-2016, 02:11 AM
RE: 4K HP 67 Games rom attached for testing - Dieter - 10-30-2016 03:52 PM

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