Writing and reading bits and memory

[andywpg]

Just a random thought here.

I'm very new to PBP (but not to microcontrollers, or BASIC for that matter), but I really don't see anywhere that you are debouncing your switches. Could this be as simple as garbage getting in from bounce?

Or am I missing something (usually the case.....)

[ERMEGM]

True, but that does not explain when holding down one button for a constantly lit LED that both will flash. I used this setup on my other program that wrote to bytes instead of bits, and it worked flawlessly.

[Dave]

Tony, Please attach the entire program in 1 segment for our viewing from configs to end...

[ERMEGM]

OK. Completed the code and things are working great now. Thanks to Darrel (DT), he explained a few things that I was doing wrong and clarified my understanding of what I thought was happening and what was really happening. After a few days of trial and error, I got it working perfectly. To clear up where the problem were, the following changes were made.

1) Didn't need to make two arrays (L_state and R_state). One array served just fine and a (+ 1) went on the second byte values so that all the left inputs went into the even memory slots and the right inputs went into the odd memory slots.

2) There was no need for four lines of code to invert the input value. The ! command took care of that (leftvalue.0[x] = !leftbutton)

3) Wasn't writing my limit to eeprom, so the value erased itself when power was removed.

So the major changes are:

EE_Limit DATA  @254,WORD 0

 Reset:
 
    OPTION_REG.7    = 0           ' Pullups  enabled
    WPU             = %000000     ' Weak Pull Up disabled because of my external pullups
    TRISIO          = %001111     ' sets pin as input (1) or output (0)
    ANSEL           = 0           ' Disable analog inputs
    CMCON0          = 7           ' Disable comparators

' -----[ Variables ]-------------------------------------------------------
 
    record        var   gpio.0    ' program button input
    leftbutton    var   gpio.1    ' left button input
    rightbutton   var   gpio.2    ' right button input   

    rightled      var   gpio.4    ' right led output
    leftled       var   gpio.5    ' left led output

    leftvalue     var   byte      ' stores the opposite value of the button
    rightvalue    var   byte      ' stores the opposite value of the button

    counter       var   word      ' counts how many bits are being used
    limit         var   word      ' stores the last count value for the loop

    x             var   byte      ' variable for bit count
    y             var   byte      ' loop variable for output flash

' -----[ Action ]----------------------------------------------------------
 
action:

    READ EE_Limit , WORD limit
 
    FOR counter = 0 TO limit Step 2' start reading bit locations
   
        read counter, leftvalue   ' read the array of bits and place in left value
        read counter + 1, rightvalue' read the array of bits and place in right value
 
        for x = 0 to 7

            leftled = leftvalue.0[x]      ' left led will mimic bit value
            rightled = rightvalue.0[x]    ' right led will mimic bit value
 
            pause 100             ' pause 1/10th of a second

        next x
 
        if record = 0 then flash  ' If program button is pressed, then
                                  ' goto program mode

    NEXT counter
 
    goto action

' -----[ Program ]---------------------------------------------------------
 
flash:

    for y = 1 to 3                ' flash outputs three times
        high leftled
        high rightled
    pause 500
        low leftled
        low rightled
    pause 500
    next y
 
    counter = 0                   ' reset counter value to 0
 
program:

        if record = 1 then action ' if the program button was momentarily pressed,
                                  ' return to action loop
    while record = 0              ' while record button is pressed, loop here
    
        if counter = 60 then finish ' if 24 seconds is reached, exit program mode
 
        for x = 0 to 7

            leftvalue.0[x] = !leftbutton ' store inverted value of leftbutton
            leftled = leftvalue.0[x]     ' display on led
  
            rightvalue.0[x] = !rightbutton ' store inverted value of rightbutton
            rightled = rightvalue.0[x]     ' display on led

            pause 100                      ' pause 1/10th of a second

        next x
 
        write counter, leftvalue
        write counter + 1, rightvalue
 
        counter = counter + 2     ' advance counter by 2

    wend

    limit = counter - 2           ' write counter value to limit
    
    WRITE EE_Limit , WORD limit

goto action                       ' go to action and run pattern

' -----[ Exit Program ]----------------------------------------------------
 
finish:
 
    while record = 0               ' loop here while program button is held
 
        low leftled
        low rightled
 
        pause 500                 ' just wait 1/2 a second
        
    wend                          ' exit loop when button is released

    limit = counter - 2           ' write counter value to limit
    
    WRITE EE_Limit , WORD limit
    
goto action                       ' return to action