calculator-like code entry with matrix keypad and display

[aratti]

Dennis, I think the bug was a missing goto. (see code added in red)

Al.

'keypad capture code begins here
          
'variables begin here
        
Array var Byte [3] 'byte array holds keypresses
A0 var byte 'counter/index
B0 var Byte 'working sum of bytes
KeyPress Var Byte ' will contain the ascii character of the key pressed passed from myvar
myvar var byte 'holds keypress byte
digit var byte 'check the number of bytes entered

start:
A0=0 'set index to 0

Ini: 'main loop

lcdout $fe,1
lcdout "enter number"
@ READKEYPAD _myvar  'read keypress variable and place in myvar
  
  LOOKUP myvar,[0,"123A456B789C*0#D"],myvar 'use lookup table to diplay proper keypress
  keypress = myvar 'pass the variable to solve strange character problem
 ' will contain the ascii character of the key pressed
  
  lcdout keypress
  pause 1000
  lcdout $fe,1  

If KeyPress = "*" then goto retry

If KeyPress = "#" then 'if # conditions begin here

if A0=2 then 'if counter is 2 then sum all bytes
B0= (Array[0]*100)+(Array[1]*10)+Array[2] 'byte sum
lcdout "3 digits ",dec B0,$0d,$0a
pause 1000
lcdout $fe,1
HSEROUT ["here is the total ",dec B0,$0d,$0a]  'send result to pc com port 
endif

if A0=1 then
B0= (Array[0]*10)+Array[1]
lcdout "2 digits " ,dec B0,$0d,$0a
pause 1000
lcdout $fe,1
HSEROUT ["here is the total ",dec B0,$0d,$0a]
endif

if A0=0 then
B0= Array[0]
lcdout "1 digit " ,dec B0,$0d,$0a
pause 1000
lcdout $fe,1
HSEROUT ["here is the total ",dec B0,$0d,$0a]
endif

A0=0

GOTO Ini

ENDIF

If A0>2 then Ini

Array[A0]=KeyPress -48
A0=A0+1
goto Ini

retry:
lcdout "retry"
pause 1000
lcdout $fe,1
A0=0
myvar=0
goto ini
goto start
end

Al.

[Dennis]

Al...

First issue is solved :-)
A0=A0-1 was needed :-) this was causing the # to be included in the array :-)
So to solve that problem just step the counter back by 1 :-)
I placed it here in the code :-)

If KeyPress = "#" then 'if # conditions begin here
   A0=A0-1

That fixed incorrect numbers issue.
So first time I power up the PIC , I enter a number (1,2 or 3 digits in size) and end with a # and whammo the correct number appears on screen :-) YAY
The problem comes in when as you enter number two .. and three etc ...
each displayed number is out !
It's because the variable does not get cleared ( not sure which one yet)
I noticed that last night (early hours of this morning :-)) and created a retry label which clears the var's and array..particularly myvar << which i think is the culprit !

Haven't tested your goto change yet ....stand by for feedback, will do it asap :-)
Al .. I just noticed you also removed the array clearance , why ? Is it because of the goto ?
Kind regards

Dennis

[Dennis]

Al...

Goto does not fix the problem
With goto in place and your code fro your last post in place unchanged...
after PIC is powered up, first number I enter is 1 and it displays as 10 (10X keypress)the number 20 is 140 ..weird !!
Ok will implement my changes and sort through it now and feedback asap :-)
Dennis

[Dennis]

Al ......

You rock !! Woooohoooo :-)

Ok GOTO was the bug !
for clearing the var's
A0=A0-1 is solution for strange numbers appearing after first keypress.
this problem is caused by the # value ( and the A,B,C,D keys would cause the same issue)

I no longer need to run the code through the retry label anymore ..yay less code! :-)

Any further thoughts mods etc ?

Dennis

[aratti]

this problem is caused by the # value ( and the A,B,C,D keys would cause the same issue

Dennis # character is intercepted by the IF/Then condition and the added " goto ini " command should have solved the issue. As far as A,B,C,D and F just place a trap with an additional IF/then condition. See the example:

If KeyPress >57 then Ini
If KeyPress = "*" then goto retry

Since only "*" ; "#" and numbers from "0" to "9" can pass the if/then condition, this should solve the problem.

Take care.

Al.

[Dennis]

Dennis # character is intercepted by the IF/Then condition and the added " goto ini " command should have solved the issue. As far as A,B,C,D and F just place a trap with an additional IF/then condition. See the example:

I get that ! :-)

But whats the > 59 doing here?

If KeyPress >59 then Ini
If KeyPress = "*" then goto retry

Since only "*" ; "#" and numbers from "0" to "9" can pass the if/then condition, this should solve the problem.

Take care.

Al.

Al.. the goto ini didn't solve the problem .. I had to add the A0=A)-1 ..one extra line no problem.
I think with * it's not a problem because as soon as * is detected the program jumps to retry ...which clears the variables ..
# is different and unfortunately does get included in the array , well at least that's what I'm guessing. Will definitely bug track to see what really happens :-) and feedback to you !

Kind regards
Dennis

[aratti]

But whats the > 59 doing here?

Sorry Dennis, I have mistaken It should be 57 (If KeyPress >57 then Ini)

57 is the ascii value for "9" so if a number is larger then 57 is not loaded into the array.

Download the zipped application I have attached, and run it on your PC. It will help you in converting ascii into decimal hex or binary and vice versa.
Just type into the box the corresponding value and press enter, you will have that value converted into the other three numerical sytem.

enjoy.

Al.

[Dennis]

Hi again

I'm wondering if this could become more dynamic in terms of the number of keypresses.
At the moment the keypresses are limited to 3, after that number the program goes a little wonky because of the B0 var which holds the sum of the 3 keypresses (hats off to Al !)
As soon as the desired/required number of keypresses has to increase, the so the need for multiplying increases .

I'm sure the program could be easily sized for a much higher number of keypresses by having more if statements and multiplies. To neaten things up perhaps a single case statement could be used and a check is kept on the index A0 in a byte.
With this in mind, the number of keypresses (number entered) could grow to the size of the number of characters on the LCD ( well almost :-))
This of course now opens the door for a PIC calculator :-)

Al,Ioannis,Joe S, Steve and Jerson ...THANK YOU for all the tips help and suggestions so far :-)
Al thank you for your patience and persisitence and of course the final piece of the puzzle.

This has taught me lot and has been a whole lot of fun!

Again thanks all of you for all the help thus far.

I will post the final code once things are neatened up and commented correctly :-) in the hopes someone finds this useful sometime !

Kind regards
Dennis