Keyboard debouncing

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akaTB
Posts: 214
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Re: Keyboard Debouncing - NOOB Question

Post by akaTB » Tue Oct 16, 2018 9:25 am

ijabbott wrote:
Tue Oct 16, 2018 7:28 am
keithdalby wrote:
Tue Oct 16, 2018 4:04 am
ijabbott wrote:
Mon Oct 15, 2018 9:52 pm
You can also press EXIT after entering a number, and it will only change the X register without disabling automatic stack lift.
I can't think of a situation where that would be useful.
It makes entering numbers on the stack behave more like RPL calculators (apart from the limited stack size).
I miss the subtle usefulness of this... :mrgreen:
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Walter
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Re: Keyboard Debouncing - NOOB Question

Post by Walter » Tue Oct 16, 2018 10:42 am

akaTB wrote:
Tue Oct 16, 2018 9:25 am
ijabbott wrote:
Tue Oct 16, 2018 7:28 am
keithdalby wrote:
Tue Oct 16, 2018 4:04 am
I can't think of a situation where that would be useful.
It makes entering numbers on the stack behave more like RPL calculators (apart from the limited stack size).
I miss the subtle usefulness of this... :mrgreen:
:lol:
DM42 SN: 00041 --- Follower of Platon.

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

StreakyCobra
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Re: Keyboard debouncing

Post by StreakyCobra » Tue Oct 16, 2018 1:59 pm

akaTB wrote:
Tue Oct 16, 2018 9:25 am
ijabbott wrote:
Tue Oct 16, 2018 7:28 am
keithdalby wrote:
Tue Oct 16, 2018 4:04 am
I can't think of a situation where that would be useful.
It makes entering numbers on the stack behave more like RPL calculators (apart from the limited stack size).
I miss the subtle usefulness of this... :mrgreen:
Actually… I find this very useful !

TL;DR: "Exit" allow you to "validate/terminate" a number without knowing if the next step is entering a new number or applying an operator.

I often find myself typing numbers at the same time that I'm thinking of a problem. For instance I open a file and I find a number, lets say 2538, so I type it in the calculator, pressing "enter" because it's the first one. I then open another file and find another number, 43, and I type it. Now I want to "validate" it because I am sure there isn't any other digit in this number. But at the same time I'm not sure if it is the number that I should divide 2538 by directly, or if I need to make a ratio first by dividing it by another third number.

So there are two options, and they both have a drawback:

1. I press "enter" after 43 -> After some thinking I decide that I should only divide 2538 by 43. Having pressed "enter" had lifted the stack, so I can not press "divide" directly because both X and Y contains 43, I have first to think about rolling down the stack, or worse if I already pressed "divide" I have to reconstruct the stack by using LastX.

2. I do not press enter after 43 -> After some thinking I decide that I should divide 43 by 7 first, before dividing 2538 by this result. I take back my calculator in hand and press 7, which now reads 437 on the X stack because the input of 43 has not been terminated. I have to clear one digit to restore 43, press "enter", and the continue by reentering 7. Also, worse, if I pressed "divide" before noticing the mistake I again have to reconstruct the stack by using LastX.

So when you are thinking about a problem on the same time than typing its calculation, your flow of thought is interrupted by "should I press «enter» or not?" after each number, what is quite annoying. By using "exit", you can "validate" each number without having to know (or think about) if the next step is a number or an operator:

- 2538 "exit"

- 43 "exit"

- Thinking about the problem, then:
1. Division is wanted: just press "divide"
2. Another number is needed, just type it: 7 "exit"

Maybe I'm doing something wrong and I'm the only one to have this problem with "enter", but for this use at least "exit" is changing my life right know :-)

keithdalby
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Re: Keyboard debouncing

Post by keithdalby » Tue Oct 16, 2018 3:16 pm

StreakyCobra wrote:
Tue Oct 16, 2018 1:59 pm
Maybe I'm doing something wrong and I'm the only one to have this problem with "enter", but for this use at least "exit" is changing my life right know
:shock: so to save you pressing extra unnecessary buttons, you press extra unnecessary buttons?

Nope, I cannot connect the dots here.

keithdalby
Posts: 498
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Re: Keyboard debouncing

Post by keithdalby » Tue Oct 16, 2018 3:18 pm

StreakyCobra wrote:
Tue Oct 16, 2018 1:59 pm
- 2538 "exit"

- 43 "exit"

- Thinking about the problem, then:
I think I must just be old-school but reaching for the calculator is the last stage in my thinking. Wouldn't dream of plugging numbers in without a clear vision of what I'm doing with them.

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ijabbott
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Location: Manchester, UK

Re: Keyboard debouncing

Post by ijabbott » Tue Oct 16, 2018 4:30 pm

Another use for "Exit" - it reformats the number you've just typed into the current display format without lifting the stack afterwards.

keithdalby
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Re: Keyboard debouncing

Post by keithdalby » Tue Oct 16, 2018 5:20 pm

ijabbott wrote:
Tue Oct 16, 2018 4:30 pm
Another use for "Exit" - it reformats the number you've just typed into the current display format without lifting the stack afterwards.
Still don't quite see the point of that

Thomas Okken
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Re: Keyboard debouncing

Post by Thomas Okken » Tue Oct 16, 2018 8:04 pm

keithdalby wrote:
Tue Oct 16, 2018 5:20 pm
ijabbott wrote:
Tue Oct 16, 2018 4:30 pm
Another use for "Exit" - it reformats the number you've just typed into the current display format without lifting the stack afterwards.
Still don't quite see the point of that
I do. It's actually something I do often enough that it has become automatic to press X<>Y X<>Y in that situation. It never occurred to me to use EXIT, probably because I had already been conditioned to think of that as "cancel and discard" by the HP-28S, before I got into the 42S. :D

rprosperi
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Re: Keyboard debouncing

Post by rprosperi » Wed Oct 17, 2018 12:22 am

Thomas Okken wrote:
Tue Oct 16, 2018 8:04 pm
keithdalby wrote:
Tue Oct 16, 2018 5:20 pm
ijabbott wrote:
Tue Oct 16, 2018 4:30 pm
Another use for "Exit" - it reformats the number you've just typed into the current display format without lifting the stack afterwards.
Still don't quite see the point of that
I do. It's actually something I do often enough that it has become automatic to press X<>Y X<>Y in that situation. It never occurred to me to use EXIT, probably because I had already been conditioned to think of that as "cancel and discard" by the HP-28S, before I got into the 42S. :D
I agree, this is useful, and surprising to discover so many years into using a 42S. While it's not something I'd use every day, it is needed sometimes; I've also learned to do X<>Y X<>Y when I want this stack condition - EXIT is even easier. Cool discovery, glad you posted it. My only question is can I unlearn using X<>Y X<>Y ?
--bob p

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Rmollov
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Location: Sydney, Australia

Re: Keyboard Debouncing - NOOB Question

Post by Rmollov » Wed Oct 17, 2018 6:29 am

Walter wrote:
Tue Oct 16, 2018 3:56 am
ijabbott wrote:
Mon Oct 15, 2018 9:52 pm
You can also press EXIT after entering a number, and it will only change the X register without disabling automatic stack lift.

This illustrates the difference in stack behaviour between ENTER and EXIT...
Never thought of using EXIT this way. Learned something new. Thanks!
+1.
I find this very useful, thanks ijabbott!
Now I remembered something similar was an option in Byron Foster's 42s - ENTER without stack lift, which I liked.
Cheers,

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