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Raw files for these HP 67 program listings ?
09-02-2016, 02:44 PM
Post: #14
RE: Raw files for these HP 67 program listings ?
(09-02-2016 06:47 AM)Dieter Wrote:  Great. I see you use the same initialization routine as my Jive Turkey version. The idea is to initialize some settings (flags, display format, user mode) which on a 67/97 is automatically done while the program card is read. If this is considered a good idea we should maybe do this for all translated programs.
Yes, sorry ... should have given you credit for this. I liked it in Jive Turkey, so I "borrowed" it. Smile

(09-02-2016 06:47 AM)Dieter Wrote:  BTW, the Blackjack program includes an infinite loop at LBL b. What's the idea behind this? It looks like this is supposed to simulate shuffling the cards: Enter a random seed and press f b, let it run for a few seconds and a new seed is generated.
Yes, the original instructions in PPCJ V3N9P38 talk about using this method to "generate" a seed.

(09-02-2016 06:47 AM)Dieter Wrote:  The 67/97 can always access 26 data registers, and it is common practice to use the higher registers A...E (i.e. R20...24). Since a lot of programs use the I-register, even the highest register number (25) is occupied even if the program otherwise merely uses R0 and R1. On the other hand memory can be limited on the 41 (especially the 41C without RAM extension), so it is a good idea to move A...E and I downwards to the lowest possible addresses. In this case (BJ) that's R10...R12 instead of D, E and I. This way only SIZE 13 is required.
Can't do that in this game ... R10-R19 are used by indirect addressing to store the "cards" that are dealt, so those registers are needed the way they are.

(09-02-2016 06:47 AM)Dieter Wrote:  In this program the HP67/97 ISZ command can be replaced with ISG followed by a dummy instruction that is never executed, as register "I" always holds a positive integer. Please note that this is not always possible. Also, instead of using ENTER for the dummy instruction, something like LBL 20 could be used. Such a label never occurs in a 67/97 program.
I actually had this as LBL14 (better to use a one-byte LBL than a multi-byte instruction)...but then you had recommended ENTER earlier, so I switched to that. I know that a single byte LBL is faster to execute than ENTER, but the way this is structured, it will never get executed, only skipped.

Thanks for the comments!
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RE: Raw files for these HP 67 program listings ? - RobertM - 09-02-2016 02:44 PM

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