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HP-65 Question - Printable Version

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HP-65 Question - Greg - 03-31-2017 08:16 PM

The HP-65 only supports one layer of subroutines. You can call one from a main program but you shouldn't call another from there.

The HP-65 Owners Manual says, if you do call lower level subroutines, the first RTN will take you back to the main program.

That suggests that starting with 0.00 in X and pressing [D] in the following:

PHP Code:
00123 LBL
002
11 A
003
01 1
004
61 : +
00524 RTN
006
23 LBL
007
12 B
008
02 2
009
61 : +
01011 A
011
03 3
012
61 : +
01324 RTN
014
23 LBL
015
13 C
016
04 4
017
61 : +
01812 B
019
05 5
020
61 : +
02124 RTN
022
23 LBL
023
14 D
024
06 6
025
61 : +
02613 C
027
07 7
028
61 : +
02924 RTN 

will produce (6 + 4 + 2 + 1 + 7 +) 20.

Does anyone have a physical HP-65 that can confirm that for me?


RE: HP-65 Question - Brad Barton - 03-31-2017 10:47 PM

(03-31-2017 08:16 PM)Greg Wrote:  will produce (6 + 4 + 2 + 1 + 7 +) 20.

Does anyone have a physical HP-65 that can confirm that for me?

Yes, the result is 20 on a physical 65. As you suspected, when the program encountered the RTN in the A subroutine, it was sent back to finish up the originally executed D subroutine, rather than run sequentially through the other subs.

Brad


RE: HP-65 Question - teenix - 03-31-2017 11:33 PM

(03-31-2017 10:47 PM)Brad Barton Wrote:  
(03-31-2017 08:16 PM)Greg Wrote:  will produce (6 + 4 + 2 + 1 + 7 +) 20.

Does anyone have a physical HP-65 that can confirm that for me?

Yes, the result is 20 on a physical 65. As you suspected, when the program encountered the RTN in the A subroutine, it was sent back to finish up the originally executed D subroutine, rather than run sequentially through the other subs.

Brad


Oops, I missed that point in the 65 manual.

I rewrote the 65 emulator's Mark and Search code to manage the subroutines in the same way. The emulator now returns 20 as well.

cheers

Tony


RE: HP-65 Question - Greg - 04-01-2017 12:59 AM

Wow that was fast Tony. I haven't even put up the fix I developed for mine yet, as I wanted to confirm the behaviour on the real thing first.

I'd noticed the problem on other emulators too. Yours always looks so good.


RE: HP-65 Question - teenix - 04-01-2017 02:34 AM

(04-01-2017 12:59 AM)Greg Wrote:  Wow that was fast Tony. I haven't even put up the fix I developed for mine yet, as I wanted to confirm the behaviour on the real thing first.

I'd noticed the problem on other emulators too. Yours always looks so good.

Hi Greg,

Thanks

It's been awhile since I got the 65 working so it was a bit of a brain strain remembering how the code for the program buffer worked :-)

Just now, I had to upload again because I forgot to update the PICmicro code for the 65 hardware emulator as well.

Cheers

Tony


RE: HP-65 Question - Brad Barton - 04-01-2017 03:30 AM

Amazing response! Thanks for updating the app so quickly.

Brad