HP Forum Archive 14

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HP 65 program tips Message #1 Posted by Ralph on 31 Jan 2005, 7:07 a.m. Somewhere on the hp65 owner's handbook it stats that when starting program execution from the keyboard pressing [R/S], the first [RTN] is ignored by the calculator and it stops at the second [RTN] found. That's true, but it seems not only the first [RTN] is ignored, also every [g][NOP] instruction found till the second [RTN]. If you try the following program (clear memory first): LBL A_ 5_ RTN_ 2_ g NOP_ +_ RTN Pressing [A] will leave the answer 5, pressing [GTO][A] and then [R/S] will leave 7! If you try this other program (clear memory first): LBL A_ 1_ RTN Switch to RUN mode and press [GTO][A] and [R/S]. The calculator passes through A and all following [g][NOP] steps on memory, back to top of memory and stops at [RTN]. If you look the stack contents the number 1 is on both X and Y registers (A has been executed two times). Supose I'm the LAST one who discovers this...

Was this the "cocked" vs. "uncocked" RTN status? Message #2 Posted by Gene on 31 Jan 2005, 9:58 a.m., in response to message #1 by Ralph I think something like this was described back in the 1974/1975 PPC Journal issues. By the way, if you DON'T have a copy of those from Jake Schwartz on CD, you're really missing a wonderful resource. :-)

Re: Was this the "cocked" vs. "uncocked" RTN status? Message #3 Posted by Ralph on 31 Jan 2005, 2:45 p.m., in response to message #2 by Gene I have the museum CD's, is this Jake Schwartz CD on them?

Link to Jake's CD ROM set of PPC Journals and more! Message #4 Posted by Gene on 31 Jan 2005, 4:30 p.m., in response to message #3 by Ralph http://www.pahhc.org/ppccdrom.htm Quite an impressive set! Gene

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