calculator-like code entry with matrix keypad and display

[Ioannis]

Hi Dennis.

Well, you think simple and in most cases this is good. But not this one!

OK. Lets take the number in your array, for example 1,2,3.

If at the end, if you add these 3 array elements together you will get 6, or binary 6 if you want.

What about 3,2,1? You will get the same, although is a completely different number. So you have to make calculations and multiply x100, x10 x1 and then sum up the result. Like we did at the second year of elementary school!

I think I did gave you a sample code for this.

Then you need some kind of LCD indexing (I covered this too, please look at your PMs).

The 1st position of the 1st row on LCDs is $80. So if you want to display at this place use:

LCDout $FE,$80+index,1st_character

Then index=index+1 and your next character goes to $80:

LCDout $FE,$80+index,2nd_character.

Of course all the above are pure an educational example. In your code you would put some traps for the index. Also you can avoid the addition in-line the LCDout command and make the index start from $80, etc all in a loop.

Sorry do not have the time to give you a complete working code.

Ioannis

[Dennis]

Hi Ioannis

Thanks a million for the reply,tips and guidance.

Yes Indeed it is your sample code as well as Aratti's that prompted this thread.

See the code snippet you sent me here (all original and intact with no changes)

 
array   var byte[5]
index   var byte
i       var byte
word_v  var word

'Get keypress
index=0

loop:
gosub key_read
if mykey=32 then loop 'No key press returns 32
array[index]=myvar
index=index+1
if index=5 then calculate_result
goto loop
...

caculate_result:
word_var=0:mult=10000
for i=index-1 to 0 step -1
    word_var=word_var*mult+array[i]
    mult=mult/10
next i
index=0
goto display_result

Ok so there were (and still are) quite a few things that didn't and don't make sense to me. And please understand I am battling to catch on to a lot of the coding tricks and reading the manual and forums and anything else that will give me some form of understanding to get functional.

I took the code snippet and dissected it, tried my best to comment it and then add it to what I had so far.
Then I compiled it solving each compile error as best I could (bearing in mind being a newbie it's difficult to spot common syntax errors and coding mistakes or areas that could be tweaked) and here is what I came up with:
[code]
'using mister_e's keypad code

array var byte[5] 'the array set at 5
index var byte
i var byte
word_var var word ' word for capturing data
mult var byte a byte for multiplication << sould this be a word

index=0 'sets index to 0

loopy: 'main loop for keypress capture


@ READKEYPAD _myvar 'read keypress variable
LOOKUP myvar,[0,"123A456B789C*0#D"],myvar 'use lookup table to dsiplay proper keypress
''if mykey=32 then loop 'No key press returns 32 '<<no idea what mykey yshould be ?? a var or a word ?and why 32?
array[index]=myvar 'build the array as the index number increases
index=index+1 'when the code runs past here add 1 to index var
if index=5 then calculate_result 'if the counter/index is 5 calculate result
goto loopy 'start the loop again


calculate_result: 'calculate results label
word_var=0 'set word variable to 0
mult=10000 'multiply result by 10000 to format number
for i=index-1 to 0 step -1 'for loop begins
word_var=word_var*mult+array[i] '
mult=mult/10
next i 'end of for statement
index=0 'set index to 0
goto display_result


goto start


display_result:
lcdout word_var
goto TX
TX:
hserout ["i got this string of numbers",$0d,$0a]
hSEROUT ["Received:",STR myvar\5,$0d,$0a]
'HSEROUT ["1st digit ", dec array(0),$0d,$0a]
'HSEROUT ["2nd digit ", dec array(1), $0d,$0a]
'HSEROUT ["3rd digit ", dec array(2), $0d,$0a]
'HSEROUT ["4th digit ", dec array(3), $0d,$0a]
'HSEROUT ["5th digit ", dec array(4), $0d,$0a]
'HSEROUT ["5th digit ", word_var, $0d,$0a]
goto clearkeys


clearkeys:
myvar = 0
goto loopy

end
[code]

So a few observations so far ...
The code allows for a # or * or A,B,C,D to be typed in, this messes everything up of course.
I have no idea what the array is holding when entering the keys.How can I display the whole array on the LCD ?
After typing in the first few characters like 00123 ended with a hash the code just does its own thing -- well at least that's how it seems.
HSEROUT works at least because everytime I press the # key I get things in MCS serial tool window, they're just wingdings and odd characters, but at least something is happening

Is there a way to capture each keystroke and then add convert them to binary and then add them together and then display the result as decimal ?

I used to have an 8-way dip switch connected to the PIC and then just set the binary number up on that and it was done ! Say for example the number 123 would be as easy as flipping the switches to 1111011 and that was that.
With a keypad I can type in the number by pressing keys 1 (wich is not 1 unless we do a look-up) same for 2 and 3 and then each number is independent and 8 bits in size.
So in order to get the number 123 into some sort of variable I have to

1.accept all keypresses into an array and filter out the keys *,#,A,B,C,D,and if any of these are encountered remove them from the array
(is there a table look-up I could implement for that ?

2.check the size of the array and if it's 3 digits then I should multiply each digit independently so 1 by 100 then 2 by 10 and 3 by 1 (or do nothing to 1)

3.once that's done I should then be able to add them together and finally derive a total ... this total can then be checked to see if it is VALID or not. For example if it is a 3 bit number and I only want a byte then it must be less than 255 otherwise generate an overflow error on lcd.

4.Finally I have the number , then it must either be converted to binary or decimal depending on where it should go.

And then to top it all off the modifiers for LCDOUT and HSERIN/OUT,HSERIN2/OUT SERIN/SEROUT SERIN2/OUT and their behaviour are all slightly different.

That said though, at least I have some code to start working with and I certainly am trying and battling along and I would really appreciate any help,tips,tricks on any of the stupid mistakes I am making or have made in the along the way to finally getting a working code/keypress/data entry system using a 4x4 or 3x3 keypad and LCD.
I was also wondering if this hasn't come up many a time before and it seems the forums are a little sparse for something that does exaclty this unless I am searching for the wrong info ?
Kind regards
Dennis

[Dennis]

Hi all

I am working on the digits now, and I think I have almost got it sorted (or not!)
I just can't see where I am going wrong and I'm sure it's the way I'm working with the array.

To somplify things I have given the variable a set number, the number 123 as in my examples above.
here's the code so far

Start:
Codex	VAR BYTE
Temp	VAR BYTE [3]
TempTot var byte 
Codex = 123
Tempx var byte
'Find character for decimal 100 column
Tempx = Codex/100 'divide Codex by 100 'cos its the digit in 100's column
Temp(0) = Tempx + 48 'add 48 to get ascii value
lcdout "first " ,temp(0)
HSEROUT ["1st digit ", Temp(0),$0d,$0a]
pause 1000

'Find character for decimal 10 column
Tempx = Codex/10 'since Codex = 123 after dividing Temp = 12
Temp(1) = Tempx//10 'Remainder is required so with Codex = 123 the number in Temp = 2
Temp(1) = Tempx + 48 'add 48 to get ascii value
 lcdout "second ",temp(1) 
HSEROUT ["2nd digit ", Temp(1),$0d,$0a]
                  pause 1000
'Find character for decimal 1 column
Tempx = Codex//10 'Get Remainder so…with Codex = 123 then Temp = 3
Temp(2) = Tempx + 48 'add 48 to get ascii value
 lcdout "third ",temp(2)
HSEROUT ["3rd digit ", Temp(2),$0d,$0a]
 pause 1000
 TempTot = Temp(0)+temp(1)+Temp(2)
  hserout ["here's the binary total ",dec temptot,$0d,$0a]
 hserout ["here's the binary total ",bin temp,$0d,$0a]
 goto start

Observations:
The first and third digits are correct , the second is a problem (and I think it's the wrong number since it shows up as a ">" character ) so this obviously messes up the total after addition which ends up as 160 as opposed to 123 :-(
Here is what I see in the MCS serial tool window

1st digit 1
2nd digit <
3rd digit 3
here's the binary total 160
here's the binary total 110001

Any help would be appreciated

Dennis

[aratti]

Dennis you can use the DIG command:

Codex  var Byte
Temp0 var Byte
Temp1 var Byte
Temp2 var Byte

Codex = 123

Temp0 = Codex DIG 0 ' set Temp0 = to digit 0 of Codex
Temp1 = Codex DIG 1 ' set Temp1 = to digit 1 of Codex
Temp2 = Codex DIG 2 ' set Temp2 = to digit 2 of Codex

That all you need.

Al.

[Archangel]

Hi Dennis,
Your code looks much more difficult to me than it needs to be, you are doing a lot of "yuck" MATH, Math not my forte' , Anyway after you
get your actual number into a variable, use the DIG function to acquire the digits.

Digit1 var byte
Digit2 var byte
Digit3 var byte
TempX var byte

Digit1 = TempX DIG 0
Digit2 = TempX DIG 1
Digit3 = TempX DIG 2

HSEROUT ["1st digit ", DEC Digit0,$0d,$0a] 'copied from your code
HSEROUT ["2nd digit ", DEC Digit1,$0d,$0a] 'copied from your code
HSEROUT ["3rd digit ", DEC Digit2,$0d,$0a] 'copied from your code

I haven't looked at your code close enough to understand what the Hex 0D and Hex 0A are for, nor have I tested this code snippet, but it should give you some ideas.
Dadgummit Al posted while I was typing! Same idea too! HiYa Al !

[Dennis]

Joe S and Al thanks so much for the reply !!

And both your codes snippets work like a charm !

I love the DIG command ...very cool !

They certainly did simplify mine somewhat :-)

OK so here's the deal so far.
The HSEROUT line is working well !
Each decimal digit is displayed correctly and in the correct order!
So a number like 123 gets sent and displayed correctly :-)

Now what remains is what I have been on about since the beginning of this thread and that is the following.

I need to get each keypress stored in an array and then 'JOIN' (either by adding them or some other method ) them up into one number..that's why I went off on a tangent in the last post.
All I would like to do is be able to send one bye or word containing the actual number keyed in.
I would like to be able to key in the number 123 (and see it on screen) and then send it as the actual number 123 decimal or binary or hex ...just not as 3 separate bytes. Consider the same thing being done with a bank of 8 dip switches ... I set the dip switches to reflect the number 123 (bin=11110111 and hex =A3) and that's what I would read in and send.
But this seems to be rather difficult to do using a keypad not so ?

Again any suggestions etc would be greatly appreciated

Kind regards
Dennis

[Byte_Butcher]

How about something like this:

keypressed var byte ' latest keypad entry
mynumber var word 'your number, built up from multiple key presses

' each time a key is pressed, do this:

mynumber = (mynumber * 10) + keypressed

Maybe?


steve

[Dennis]

Tried that ... it yeilds undesirable results .. and with each keypress a different value appears in MCS serial tool window :-(

the numbers are 34113
the numbers are 13500
the numbers are 3978
the numbers are 39830
the numbers are 5134

This is probably because the number is continuously multiplied each time the program loops at each keypress ... and the word value aslo can only store two bytes (16 bits)
This is how I tried your suggestion

'end of variables
    
           Pause 2000       ' Wait for LCD to startup
Start:

  @ READKEYPAD _myvar  'read keypress variable and place in myvar
  
  LOOKUP myvar,[0,"123A456B789C*0#D"],myvar 'use lookup table to display proper keypress
           
               
                    

                   lcdout myvar
                   lcdout $fe,1
                   pause 1000
mynumber = (mynumber * 10) + myvar 
lcdout "my number ", dec mynumber
hserout ["the numbers are " ,dec mynumber,$0d,$0a]

The plan is along the right lines though!

1.Check keypress to see if it's valid (0-9,A,B,C,D)
2.Store each vaild keypress eg. 1,2,3 (number is 123) <<<<<<<<<<<THIS IS WHERE I HAVE A PROBLEM DON'T KNOW HOW TO WORK WITH THE ARRAY!
3.Check for # character which denotes a valid input
4.Take first character and (LSB) and multiply it by 1(byte 1)
5.Take next character and multiply by 10 (byte 2)
6.Take next character and multiply by 100 (byte 3)
7. Now add them up (in this example 100+20+3 = 123)
8.Check that number is valid ... <255 since it must be max one byte (8 bits)
123 is valid since it's less than 255
9.Display and send the number

Those are the steps I need to go through :-)

Hope that helps

Kind regards
Dennis