Keyboard debouncing

If you're having problems with the hardware of a DM42, post about them here.
cdmackay
Posts: 49
Joined: Fri Oct 05, 2018 6:33 pm
Location: Cambridge, UK
Contact:

Re: Keyboard debouncing

Post by cdmackay » Wed Feb 06, 2019 2:44 pm

rprosperi wrote:
Wed Feb 06, 2019 2:47 am
I'm not 100% why folks are advocating these alternates (there seem to be multiple points being made) but the main difference is that [Enter] disables stack-lift, so the next thing entered replaces X without pushing the stack up, while the other methods terminate entry with stack lift enabled. To me, there are corner cases where this can make a difference, but typically it's not important. The usual reason folks pursue this is if they learned RPL before RPN, where all terminated entries always enable stack lift. These tricks better simulate the behavior of RPL.
thanks Bob!
Cambridge, UK
41CL, 12C, DM15,16,42, 30b (WP 34S), 17B, 28S, 48GX, 50g, 50g (newRPL), Prime G2
various Casio, Rockwell 18R :)

User avatar
Walter
Posts: 915
Joined: Tue May 02, 2017 9:13 am
Location: Close to FRA, Germany

Re: Keyboard debouncing

Post by Walter » Wed Feb 06, 2019 3:07 pm

akaTB wrote:
Wed Feb 06, 2019 6:52 am
rprosperi wrote:
Wed Feb 06, 2019 2:47 am

The usual reason folks pursue this is if they learned RPL before RPN, where all terminated entries always enable stack lift. These tricks better simulate the behavior of RPL.
Correct, and that's the main reason why we should avoid this and show them the light. :lol:
One more reason why WP calculators stick to RPN. 8-)

IIRC, far less people complained about ENTER at times when one-line displays were standard. More than two output lines seem to add confusion instead of enlightenment. Just an observation. ;)
DM42 SN: 00041 --- Follower of Platon.

HP-35, HP-45, ..., HP-50, WP 34S, WP 31S, DM16L

rprosperi
Posts: 428
Joined: Mon Apr 24, 2017 5:48 pm
Location: New York

Re: Keyboard debouncing

Post by rprosperi » Wed Feb 06, 2019 9:31 pm

Walter wrote:
Wed Feb 06, 2019 3:07 pm
IIRC, far less people complained about ENTER at times when one-line displays were standard. More than two output lines seem to add confusion instead of enlightenment. Just an observation. ;)
I've noticed this too Walter, quite weird and unexpected; it would seem that being able to view more of the stack would provide confirmation of what one has presumably understood all along. But again, folks that started on RPL have always seen the entire stack, plus never needed to learn the subtleties of Stack-lift enable, -disable, etc. I suppose the lesson here is that with only 1-level visible, one had to spend more time thinking about what was where in the stack, rather than directly observing it.
--bob p

DM42: β00071 & 00282

User avatar
Walter
Posts: 915
Joined: Tue May 02, 2017 9:13 am
Location: Close to FRA, Germany

Re: Keyboard debouncing

Post by Walter » Wed Feb 06, 2019 10:07 pm

rprosperi wrote:
Wed Feb 06, 2019 9:31 pm
Walter wrote:
Wed Feb 06, 2019 3:07 pm
IIRC, far less people complained about ENTER at times when one-line displays were standard. More than two output lines seem to add confusion instead of enlightenment. Just an observation. ;)
I've noticed this too Walter, quite weird and unexpected; it would seem that being able to view more of the stack would provide confirmation of what one has presumably understood all along. But again, folks that started on RPL have always seen the entire stack, plus never needed to learn the subtleties of Stack-lift enable, -disable, etc. I suppose the lesson here is that with only 1-level visible, one had to spend more time thinking about what was where in the stack, rather than directly observing it.
Yeah, thinking often helps. ;) BTW, a similar development was observed few decades earlier: with electronic calculators making slide rules obsolete, the abilities of estimating the correct order of magnitude of results faded. Unused neurons look for alternative tasks - train your brain!
DM42 SN: 00041 --- Follower of Platon.

HP-35, HP-45, ..., HP-50, WP 34S, WP 31S, DM16L

Post Reply