Change On Interrupt, PIC16F884

[elec_mech]

Adam,

I see what you mean with the DEFINE, oops! Thanks for the catch. I see what you mean with colors. Is this better?

INCLUDE "modedefs.bas"
PORTA = $00 ' Set all port a pins to low
PORTB = $00 ' Set all port b pins to low
PORTC = $00 ' Set all port c pins to low
PORTD = $00 ' Set all port d pins to low
PORTE = $00 ' Set all port e pins to low

asm ; The following code is assembly, not Basic
__CONFIG _CONFIG1, _INTOSCIO & _WDT_OFF & _PWRTE_ON & _CP_OFF & _BOR_OFF & _IESO_OFF & _FCMEN_OFF & _LVP_OFF
; Use internal oscillator & make both, OSC pins I/Os, turn off watchdog timer, enable Power-up timer,
; code protection off, brown-out off, disable switch over mode, turn off failsafe monitor,
; low voltage programming off
endasm ' End assembly code

ADCON0.0 = 0 ; Make all analog pins digital I/Os
CM1CON0.7 = 0 ; Disable comparator C1
CM2CON0.7 = 0 ; Disable comparator C2
OSCCON.6 = 1 ; Set the internal oscillator to 8MHz
OSCCON.5 = 1 ; Set the internal oscillator to 8MHz
OSCCON.4 = 1 ; Set the internal oscillator to 8MHz
WDTCON.0 = 0 ; Disable the watchdog timer
ANSEL = %00000000 ; Set all analog pins on port a to digital I/O
ANSELH = %00000000 ; Set all analog pins on port b to digital I/O

DEFINE OSC 8 ' Tell the program the oscillator is running at 8 MHz
TRISA = %00000000 ' Make all port a pins outputs
TRISB = %00001111 ' Make port b pins 0-3 inputs and the rest as outputs
TRISC = %00000000 ' Make all port c pins outputs
TRISD = %00000000 ' Make all port d pins outputs
TRISE = %00000000 ' Make all port e pins outputs
PORTA = $00 ' Set all port a pins to low
PORTB = $00 ' Set all port b pins to low
PORTC = $00 ' Set all port c pins to low
PORTD = $00 ' Set all port d pins to low
PORTE = $00 ' Set all port e pins to low
'Variables**************************************** ************************************************** *
b0 VAR byte ' Required byte variable for toggle button
'************************************************* ************************************************** *
INITIALIZE: ' Initialize Routine
INTCON.0 = 0 ' Clear the interrupt-on-change flag
On Interrupt goto Halt ' Once an active interrupt port is enabled, go to the Halt routine
INTCON = %10001000 ' Enable global interrupts, Enable interrupt-on-change on Port b
IOCB = %00000011 ' Enable interrupt-on-change on RB0-RB3
PORTE.1 = 0 ' Make sure LED on PORTE.1 is off
PORTE.2 = 0 ' Make sure LED on PORTE.2 is off
GOTO MAIN ' Go to Main routine
'************************************************* ************************************************** *
MAIN:
HIGH PORTE.0
PAUSE 500
LOW PORTE.0
PAUSE 500
GOTO MAIN
'*************************************************
DISABLE ' do NOT place interrupt checking code below
Halt: ' Halt Routine
IF PORTB.0 = 0 THEN
WHILE PORTB.0=0 ' wait for button release & end mismatch condition on portb
WEND
PAUSE 20 ' Debounce delay
HIGH PORTE.1
LOW PORTE.2
ENDIF
IF PORTB.1 = 0 THEN
WHILE PORTB.1=0 ' wait for button release & end mismatch condition on portb
WEND
PAUSE 20 ' Debounce delay
LOW PORTE.1
HIGH PORTE.2
ENDIF

' IF PORTB.0 = 0 THEN
' ' PAUSE 20
' ' IF PORTB.0 = 0 THEN
' HIGH PORTE.1
' LOW PORTE.2
' ' ENDIF
' ENDIF
'
' IF PORTB.1 = 0 THEN
' ' PAUSE 20
' ' IF PORTB.1 = 0 THEN
' LOW PORTE.1
' HIGH PORTE.2
' ' ENDIF
' ENDIF

INTCON.0 = 0 ' Clear the interrupt-on-change flag
RESUME ' Go to Main routine
ENABLE ' Enable all active interrupts

[Pic_User]

Adam,
I see what you mean with the DEFINE, oops! Thanks for the catch. I see what you mean with colors. Is this better?

It is better! But the idea is to copy from your editor, paste into a code box. So the indents and formatting look more like the original. Sometimes the forum changes the formatting. I was not sure the lowercase define was in your original or being changed by the forum. It changes a lot of things “for you” I wish I knew more about PBP to really help you on your real question.
-Adam-

[mister_e]

with code bracket
I type
[code]
i now paste my code here
then i type [/code]

we got

        asm ; The following code is assembly, not Basic
                __CONFIG _CONFIG1, _INTOSCIO & _WDT_OFF & _PWRTE_ON & _CP_OFF & _BOR_OFF & _IESO_OFF & _FCMEN_OFF & _LVP_OFF
                ; Use internal oscillator & make both, OSC pins I/Os, turn off watchdog timer, enable Power-up timer,
                ; code protection off, brown-out off, disable switch over mode, turn off failsafe monitor,
                ; low voltage programming off
        endasm ' End assembly code

        define OSC 8        ' Tell the program the oscillator is running at 8 MHz
        OSCCON.6 = 1        ; Set the internal oscillator to 8MHz
        OSCCON.5 = 1        ; Set the internal oscillator to 8MHz
        OSCCON.4 = 1        ; Set the internal oscillator to 8MHz

        PORTA = $00         ' Set all port a pins to low
        PORTB = $00         ' Set all port b pins to low
        PORTC = $00         ' Set all port c pins to low
        PORTD = $00         ' Set all port d pins to low
        PORTE = $00         ' Set all port e pins to low

        TRISA = %00000000   ' Make all port a pins outputs
        TRISB = %00001111   ' Make port b pins 0-3 inputs and the rest as outputs
        TRISC = %00000000   ' Make all port c pins outputs
        TRISD = %00000000   ' Make all port d pins outputs
        TRISE = %00000000   ' Make all port e pins outputs
        
        ADCON0.0 = 0        ; Make all analog pins digital I/Os
        CM1CON0.7 = 0       ; Disable comparator C1
        CM2CON0.7 = 0       ; Disable comparator C2
        WDTCON.0 = 0        ; Disable the watchdog timer
        ANSEL = %00000000   ; Set all analog pins on port a to digital I/O
        ANSELH = %00000000  ; Set all analog pins on port b to digital I/O
        
        INCLUDE "modedefs.bas"

'Variables*****************************************************************************************
        b0 VAR byte         ' Required byte variable for toggle button


'**************************************************************************************************
INITIALIZE:                 ' Initialize Routine
        INTCON.0 = 0        ' Clear the interrupt-on-change flag
        On Interrupt goto Halt ' Once an active interrupt port is enabled, go to the Halt routine
        INTCON = %10001000  ' Enable global interrupts, Enable interrupt-on-change on Port b
        IOCB = %00000011    ' Enable interrupt-on-change on RB0-RB3
        PORTE.1 = 0         ' Make sure LED on PORTE.1 is off
        PORTE.2 = 0         ' Make sure LED on PORTE.2 is off


'*************************************************************************************************** *
MAIN:
        HIGH PORTE.0
        PAUSE 500
        LOW PORTE.0
        PAUSE 500
        GOTO MAIN


'*************************************************
        DISABLE         ' do NOT place interrupt checking code below
        
Halt:   ' Halt Routine
        IF PORTB.0 = 0 THEN
                WHILE PORTB.0=0 ' wait for button release & end mismatch condition on portb
                WEND
                PAUSE 20        ' Debounce delay
                HIGH PORTE.1
                LOW PORTE.2
                ENDIF
                
        IF PORTB.1 = 0 THEN
                WHILE PORTB.1=0 ' wait for button release & end mismatch condition on portb
                WEND            
                PAUSE 20        ' Debounce delay
                LOW PORTE.1
                HIGH PORTE.2
                ENDIF
       
        INTCON.0 = 0            ' Clear the interrupt-on-change flag
        RESUME                  ' Go to Main routine
        ENABLE                  ' Enable all active interrupts

with colors, following the following thread
http://www.picbasic.co.uk/forum/show...ht=show+colors

we got

<font color="#000000">        <font color="#000080">ASM </font><font color="#008000">; The following code is assembly, not Basic
                </font><font color="#000080">__CONFIG _CONFIG1, _INTOSCIO &amp; _WDT_OFF &amp; _PWRTE_ON &amp; _CP_OFF &amp; _BOR_OFF &amp; _IESO_OFF &amp; _FCMEN_OFF &amp; _LVP_OFF
                </font><font color="#008000">; Use internal oscillator &amp; make both, OSC pins I/Os, turn off watchdog timer, enable Power-up timer,
                ; code protection off, brown-out off, disable switch over mode, turn off failsafe monitor,
                ; low voltage programming off
        </font><font color="#000080">ENDASM </font><font color="#008000">' End assembly code

        </font><font color="#000080">DEFINE </font>OSC 8        <font color="#008000">' Tell the program the oscillator is running at 8 MHz
        </font>OSCCON.6 = 1        <font color="#008000">; Set the internal oscillator to 8MHz
        </font>OSCCON.5 = 1        <font color="#008000">; Set the internal oscillator to 8MHz
        </font>OSCCON.4 = 1        <font color="#008000">; Set the internal oscillator to 8MHz

        </font>PORTA = $00         <font color="#008000">' Set all port a pins to low
        </font>PORTB = $00         <font color="#008000">' Set all port b pins to low
        </font>PORTC = $00         <font color="#008000">' Set all port c pins to low
        </font>PORTD = $00         <font color="#008000">' Set all port d pins to low
        </font>PORTE = $00         <font color="#008000">' Set all port e pins to low

        </font>TRISA = %00000000   <font color="#008000">' Make all port a pins outputs
        </font>TRISB = %00001111   <font color="#008000">' Make port b pins 0-3 inputs and the rest as outputs
        </font>TRISC = %00000000   <font color="#008000">' Make all port c pins outputs
        </font>TRISD = %00000000   <font color="#008000">' Make all port d pins outputs
        </font>TRISE = %00000000   <font color="#008000">' Make all port e pins outputs
        
        </font>ADCON0.0 = 0        <font color="#008000">; Make all analog pins digital I/Os
        </font>CM1CON0.7 = 0       <font color="#008000">; Disable comparator C1
        </font>CM2CON0.7 = 0       <font color="#008000">; Disable comparator C2
        </font>WDTCON.0 = 0        <font color="#008000">; Disable the watchdog timer
        </font>ANSEL = %00000000   <font color="#008000">; Set all analog pins on port a to digital I/O
        </font>ANSELH = %00000000  <font color="#008000">; Set all analog pins on port b to digital I/O
        
        </font><font color="#000080">INCLUDE </font>&quot;modedefs.bas&quot;

<font color="#008000">'Variables*****************************************************************************************
        </font>b0 <font color="#000080">VAR BYTE         </font><font color="#008000">' Required byte variable for toggle button


'**************************************************************************************************
</font>INITIALIZE:                 <font color="#008000">' Initialize Routine
        </font>INTCON.0 = 0        <font color="#008000">' Clear the interrupt-on-change flag
        </font><font color="#000080">ON INTERRUPT GOTO </font>Halt <font color="#008000">' Once an active interrupt port is enabled, go to the Halt routine
        </font>INTCON = %10001000  <font color="#008000">' Enable global interrupts, Enable interrupt-on-change on Port b
        </font>IOCB = %00000011    <font color="#008000">' Enable interrupt-on-change on RB0-RB3
        </font>PORTE.1 = 0         <font color="#008000">' Make sure LED on PORTE.1 is off
        </font>PORTE.2 = 0         <font color="#008000">' Make sure LED on PORTE.2 is off


'*************************************************************************************************** *
</font>MAIN:
        <font color="#000080">HIGH </font>PORTE.0
        <font color="#000080">PAUSE </font>500
        <font color="#000080">LOW </font>PORTE.0
        <font color="#000080">PAUSE </font>500
        <font color="#000080">GOTO </font>MAIN


<font color="#008000">'*************************************************
        </font><font color="#000080">DISABLE         </font><font color="#008000">' do NOT place interrupt checking code below
        
</font>Halt:   <font color="#008000">' Halt Routine
        </font><font color="#000080">IF </font>PORTB.0 = 0 <font color="#000080">THEN
                WHILE </font>PORTB.0=0 <font color="#008000">' wait for button release &amp; end mismatch condition on portb
                </font><font color="#000080">WEND
                PAUSE </font>20        <font color="#008000">' Debounce delay
                </font><font color="#000080">HIGH </font>PORTE.1
                <font color="#000080">LOW </font>PORTE.2
                <font color="#000080">ENDIF
                
        IF </font>PORTB.1 = 0 <font color="#000080">THEN
                WHILE </font>PORTB.1=0 <font color="#008000">' wait for button release &amp; end mismatch condition on portb
                </font><font color="#000080">WEND            
                PAUSE </font>20        <font color="#008000">' Debounce delay
                </font><font color="#000080">LOW </font>PORTE.1
                <font color="#000080">HIGH </font>PORTE.2
                <font color="#000080">ENDIF
       
        </font>INTCON.0 = 0            <font color="#008000">' Clear the interrupt-on-change flag
        </font><font color="#000080">RESUME                  </font><font color="#008000">' Go to Main routine
        </font><font color="#000080">ENABLE                  </font><font color="#008000">' Enable all active interrupts
</font>

Read your datasheet about Interrupt on change. I haven't done myself, but I bet you should read the whole, save it to a variable, then play with this variable.

Probably not a bad idea, to do the same thing before ON INTERRUPT.. read the whole port, save it to a dummy variable, etc.

HTH

[elec_mech]

Alright, I got smart and have an LED coming on whenever the interrupt routine is entered and guess what? The program always goes into the interrupt routine whenever I press a button. The bad news is that the program doesn't seem to be able to determine which switch is pressed fast enough. Again, if I hold the switch down for a second or more, it knows which switch is pressed. But more often than not, I just press the button as anyone would and I see the LED come on indicating the interrupt routine was entered, but the other LEDs don't toggle most of the time. I suspect that the program is dragging somewhere, but I don't know why the program can pick up a change on PORTB but doesn't have the time to determine which input was tripped. Any suggestions? Modified code below.

'************************************************* ************************************************** *
MAIN:
' HIGH PORTE.0
PAUSE 500
LOW PORTE.0
' PAUSE 500
GOTO MAIN
'*************************************************
DISABLE ' do NOT place interrupt checking code below
Halt: ' Halt Routine
HIGH PORTE.0
IF PORTB.0 = 0 THEN
WHILE PORTB.0=0 ' wait for button release & end mismatch condition on portb
WEND
PAUSE 20 ' Debounce delay
HIGH PORTE.1
LOW PORTE.2
ENDIF
IF PORTB.1 = 0 THEN
WHILE PORTB.1=0 ' wait for button release & end mismatch condition on portb
WEND
PAUSE 20 ' Debounce delay
LOW PORTE.1
HIGH PORTE.2
ENDIF

INTCON.0 = 0 ' Clear the interrupt-on-change flag
RESUME Main ' Go to Main routine
ENABLE ' Enable all active interrupts

[Bruce]

You have 500mS delays before your interrupt can even be processed. Unless someone
presses & holds a button, it may be quite a long time before you enter your interrupt
handler.

Reduce your pause times by using a loop with PAUSEUS until your 500mS delay period
expires. Then you only have a few uS before PBP will jump to your int handler, and you
can read the whole port in the first line, save it to a variable, then make a decision on
which switch was pressed.

[Charles Linquis]

Just a suggestion - use Darrel Taylor's Instant Interrupts. If you use that, you don't have to worry about PAUSE. The interrupt routine will be entered whenever the button is pushed - even in the middle of a PAUSE routine. In the end, it is a much cleaner solution than ON INTERRUPT GOTO - believe me.

[elec_mech]

Ahh, I was wondering if that might impact it. So, an external interrupt will not interrupt the program while executing a pause command? Is that due to the way PBP works? If I were to go so far as to program in assembly, it's been a while, I would assume I could interrupt a timer function with an external interrupt. Okay though, I see what you mean.

Alright, I gave it shot and eureka, it works! Thank you Bruce! Here's the updated code.

INCLUDE "modedefs.bas"
PORTA = $00 ' Set all port a pins to low
PORTB = $00 ' Set all port b pins to low
PORTC = $00 ' Set all port c pins to low
PORTD = $00 ' Set all port d pins to low
PORTE = $00 ' Set all port e pins to low

asm ; The following code is assembly, not Basic
__CONFIG _CONFIG1, _INTOSCIO & _WDT_OFF & _PWRTE_ON & _CP_OFF & _BOR_OFF & _IESO_OFF & _FCMEN_OFF & _LVP_OFF
; Use internal oscillator & make both, OSC pins I/Os, turn off watchdog timer, enable Power-up timer,
; code protection off, brown-out off, disable switch over mode, turn off failsafe monitor,
; low voltage programming off
endasm ' End assembly code

ADCON0.0 = 0 ; Make all analog pins digital I/Os
CM1CON0.7 = 0 ; Disable comparator C1
CM2CON0.7 = 0 ; Disable comparator C2
OSCCON.6 = 1 ; Set the internal oscillator to 8MHz
OSCCON.5 = 1 ; Set the internal oscillator to 8MHz
OSCCON.4 = 1 ; Set the internal oscillator to 8MHz
WDTCON.0 = 0 ; Disable the watchdog timer
ANSEL = %00000000 ; Set all analog pins on port a to digital I/O
ANSELH = %00000000 ; Set all analog pins on port b to digital I/O

DEFINE OSC 8 ' Tell the program the oscillator is running at 8 MHz
TRISA = %00000000 ' Make all port a pins outputs
TRISB = %00001111 ' Make port b pins 0-3 inputs and the rest as outputs
TRISC = %00000000 ' Make all port c pins outputs
TRISD = %00000000 ' Make all port d pins outputs
TRISE = %00000000 ' Make all port e pins outputs
PORTA = $00 ' Set all port a pins to low
PORTB = $00 ' Set all port b pins to low
PORTC = $00 ' Set all port c pins to low
PORTD = $00 ' Set all port d pins to low
PORTE = $00 ' Set all port e pins to low
'Variables**************************************** ************************************************** *
b0 VAR byte ' Required byte variable for toggle button
i var word
temp var byte
'************************************************* ************************************************** *
INITIALIZE: ' Initialize Routine
INTCON.0 = 0 ' Clear the interrupt-on-change flag
On Interrupt goto Halt ' Once an active interrupt port is enabled, go to the Halt routine
INTCON = %10001000 ' Enable global interrupts, Enable interrupt-on-change on Port b
IOCB = %00000011 ' Enable interrupt-on-change on RB0-RB3
PORTE.1 = 0 ' Make sure LED on PORTE.1 is off
PORTE.2 = 0 ' Make sure LED on PORTE.2 is off
GOTO MAIN ' Go to Main routine
'************************************************* ************************************************** *
MAIN:
HIGH PORTE.0
FOR i = 1 to 5000
PAUSEUS 100
NEXT
LOW PORTE.0
FOR i = 1 to 5000
PAUSEUS 100
NEXT
GOTO MAIN
'*************************************************
DISABLE ' do NOT place interrupt checking code below
Halt: ' Halt Routine
temp = PORTB
IF temp.0 = 0 THEN
WHILE PORTB.0=0 ' wait for button release & end mismatch condition on portb
WEND
PAUSE 20 ' Debounce delay
HIGH PORTE.1
LOW PORTE.2
ENDIF
IF temp.1 = 0 THEN
WHILE PORTB.1=0 ' wait for button release & end mismatch condition on portb
WEND
PAUSE 20 ' Debounce delay
LOW PORTE.1
HIGH PORTE.2
ENDIF
INTCON.0 = 0 ' Clear the interrupt-on-change flag
RESUME ' Resume wherever program left off at
ENABLE ' Enable all active interrupts

Sorry, I tried the Save As in html to get the color, but I can't save it as html from MPLAB.

I assume the while loop and 20ms debounce pause are still good to have.

Charles, I tried using Darrel Teylor's Instant Interrupts without success. I attempted to use the RBC_INT. It didn't work and I read that that command is only designed for ports b4-7. Then I attempted to use INT0_INT and INT1_INT for ports b0 and b1, respectively, but no luck there either. I'm not sure if I'm doing something wrong or if I need configure something. I love the concept, but I wanted to figure out how to fix the PBP interrupt version I'm familar with before I try figuring out a new method. I'm open to suggestions if you have any. Thank you for the suggestion. I definitely want to play with Darrel's solution once I've got this licked.

[Archangel]

Ahh, I was wondering if that might impact it. So, an external interrupt will not interrupt the program while executing a pause command? Is that due to the way PBP works? If I were to go so far as to program in assembly, it's been a while, I would assume I could interrupt a timer function with an external interrupt. Okay though, I see what you mean.

Alright, I gave it shot and eureka, it works! Thank you Bruce! Here's the updated code.

It's due to PBP interrupts being a Psudo interrupt, it detects the hardware interrupt, puts a request on the stack and waits for an opportunity, Whereas an assembly interrupt is like cops, break in and announce it's arrival.