Interrupt won't execute.

[bison_bloke]

Thanks Dwight, I tried that, but it didn't help. The interrupt isn't happening at all.

[Heckler]

Just thinking out loud now...

some possibilities:
What is the source for the timer clock?
What is the prescaler value?
Did you properly enable the timer interrupt?
(with the 12f683 it is the PIE1 reg)
INTCON reg setup correctly?

I can't remember exactly why right now... but at the end of my timer interrupt service routine I had these two lines, which clears bit 0 of these two registers. I think it clears the interupt flags so that when the "ENABLE" statement is hit(at then end of the interrupt handler code), it does not immediatly, falsely, re-interrupt.

intcon.0 = 0
   PIR1.0 = 0

These are just my musings and I too am a newbie at this stuff
If all else fails then write a small snippet of code that just tests one portion of your code to try and narrow the problem down.

Do not forget to make the chip .pdf manual your best friend... you must, must, must read it! (a section at a time) go to the section on timers and on interupts and see what it tells you.

That, in my opinion, is really the BIG difference between the versatility of the PIC micros and of something like the basic stamp. The PIC has much to offer and therefore much to configure correctly.

Good luck
Dwight

[bison_bloke]

What is the source for the timer clock?

Internal oscillator, I think I've selected this properly, but I'm not sure.

What is the prescaler value?

It should be 8 - I hope.

Did you properly enable the timer interrupt?

I tried to. I suspect this is where I need the help.

INTCON reg setup correctly?

Once again, I'm not sure. I tried to.

Do not forget to make the chip .pdf manual your best friend... you must, must, must read it!

I've read this, and other sections many times, but I really am starting from scratch here. I've nutted out quite a few things, but so much of the terminology is unfamiliar to me that it's not always clear.

[Heckler]

Below is text copied from the 16f690 docs...

Section 6.7 Timer1 Interrupt
The Timer1 register pair (TMR1H:TMR1L) increments
to FFFFh and rolls over to 0000h. When Timer1 rolls
over, the Timer1 interrupt flag bit of the PIR1 register is
set. To enable the interrupt on rollover, you must set
these bits:
• TMR1ON bit of the T1CON register
• TMR1IE bit of the PIE1 register
• PEIE bit of the INTCON register
• GIE bit of the INTCON register
The interrupt is cleared by clearing the TMR1IF bit in
the Interrupt Service Routine.

Note: The TMR1H:TTMR1L register pair and the
TMR1IF bit should be cleared before
enabling interrupts.

I feel your pain!

Dwight

[LinkMTech]

Can't help with the interupts for now but will offer a suggestion for your A/D part. I'm not sure how you got the numbers to compare and set the servo output values. Your variable "temp" will only get a value somewhere between 0 and 1023 due to the 10bit A/D.

FINDPROGRAM                'SELECTS BETWEEN SEVERAL TYPES OF MOTION
    ADCIN 10, TEMP          'READ CHANNEL 10 TO TEMP
    IF TEMP = 15000 THEN POSITION = 125                    'USES VOLTAGE DIVIDER TO
    IF TEMP  15000 AND TEMP = 22000 THEN POSITION = 150   'VARY THE VOLTAGE ON CH10.
    IF TEMP  22000 AND TEMP = 35000 THEN POSITION = 175   'THIS CONVERTS AND STORES
    IF TEMP  35000 AND TEMP = 47000 THEN POSITION = 200   'TO 'TEMP'.
    IF TEMP  47000 AND TEMP = 60000 THEN POSITION = 225   
    IF TEMP  60000 THEN POSITION = 250
    GOSUB SETPULSE   
RETURN

I would suggest using the SELECT CASE to compare your 6 A/D value possibilities. List the "Values" in ascending order and this will set your "POSITION" value as needed.

FINDPROGRAM                'SELECTS BETWEEN SEVERAL TYPES OF MOTION
    ADCIN 10, TEMP   ' Note: Value returned will be anywhere from 0 to 1023
    SELECT CASE TEMP
        CASE Value1: POSITION = 125         'TEMP = Value1, lowest value 
        CASE is <= Value2: POSITION = 150   'TEMP <= Value2
        CASE IS <= Value3: POSITION = 175   'TEMP <= Value3
        CASE IS <= Value4: POSITION = 200   'TEMP <= Value4
        CASE IS <= Value5: POSITION = 225   'TEMP <= Value5
        CASE Value6: POSITION = 250         'TEMP = Value6, highest value
    END SELECT        
    GOSUB SETPULSE   
RETURN

[bison_bloke]

Thanks for the input Link, I'll have to have a look at that code, it looks smaller than mine.

The way I've done it works currently though. When I cut and pasted code it seems some characters didn't come across for some reason. the individual lines should look more like:

IF TEMP > 22000 AND TEMP <= 35000 THEN POSITION = 175

I don't know why, but the ADC values do come out between those values; they go all the way up to 65535 with full voltage. I tried to calculate how they'd come out before I coded it, but ended up just adjusting them after seeing the output. If anyone knows why that'd be interesting.

Still need help with the interrupts though.

I've since added every single registry setting I could find in, and i got it off the ground, but it's giving me very strange results. I'll post more details once the kids are in bed.

[Acetronics2]

Hi, BB

your code doesn't compile at all ...

from MCS ...

FATAL ERROR: Too many errors. (21)
ERROR Line 53: Bad expression or missing THEN. (AdCServo.pbp)
ERROR Line 53: Syntax error. (AdCServo.pbp)
ERROR Line 54: Bad expression or missing THEN. (AdCServo.pbp)
ERROR Line 54: Syntax error. (AdCServo.pbp)
ERROR Line 55: Bad expression or missing THEN. (AdCServo.pbp)
ERROR Line 55: Syntax error. (AdCServo.pbp)
ERROR Line 56: Bad expression or missing THEN. (AdCServo.pbp)
ERROR Line 56: Syntax error. (AdCServo.pbp)
ERROR Line 57: Bad expression or missing THEN. (AdCServo.pbp)
ERROR Line 64: Bad expression. (AdCServo.pbp)
ERROR Line 65: Bad expression. (AdCServo.pbp)
ERROR Line 66: Bad expression. (AdCServo.pbp)
ERROR Line 71: Bad expression. (AdCServo.pbp)
ERROR Line 72: Bad expression. (AdCServo.pbp)
ERROR Line 73: Bad expression. (AdCServo.pbp)
ERROR Line 82: Bad expression. (AdCServo.pbp)
ERROR Line 83: Bad expression. (AdCServo.pbp)
ERROR Line 91: Bad expression. (AdCServo.pbp)
ERROR Line 101: Bad expression. (AdCServo.pbp)

add to that most of the operators and tokens are missing, your TMR1 calculations are false ( Where's the prescaler you've set to 8, gone ??? ), TMROFF calculations also false, your HSEROUT command syntax is not correct ...
and the servo pulse values do not match 0 and 180° positions !

Ok, I stop here ...

You'd better rewrite your PROJECT on a white sheet from very start ...

Would be much better ( and quicker ) than trying to correct what you've done ...

AND I did forget last, but not least ... do not use " ON INTERRUPT " as timing is critical here ... only ASM interrupts will fit here ... IF you insist on using interrupts - that are not at all compulsory in such a project -


Alain

[bison_bloke]

As mentioned above, I've added every single register entry that I could find that was related to timer1.

The interrupt now executes, but I'm getting weird results.

Firstly here's the code for the registry entrys I've added:

T1CON  = %00110001          'ENABLE X,X,PRESCALER = 8,X,X,X,TMR1ON 
INTCON     = %11001000      'ENABLE GIE,PEIE,x,x,GPIE,x,x,x
GIE         var INTCON.7
PEIE        var INTCON.6
TMR1IE      var PIE1.0
TMR1ON      var T1CON.0
TMR1IE = 1                  '
PEIE = 1                    'WHO KNOWS
GIE = 1                     'WHAT ALL OF 
PIR1.0 = 0                  'THESE DO, BUT IT 
TMR1H = 0                   'DIDN'T START 
TMR1L = 0                   'WITHOUT THEM.

I'm thinking I've added too many, but I don't really know how they work - even after reading the datasheet several times. If anyone has any comments to make about these I'd be most grateful, I really am trying to learn.

Here's the interrupt routine again:

DISABLE' INTERRUPT
INTCODE:
    IF SERVO1 = 0 THEN
        HSEROUT ["FIRST IF - POSITION: ",DEC POSITION,10]
        TMR1H = ((65535 - POSITION)/256)            'EXTRACT HIGH BYTE INTO TIMER1
        TMR1L = ((65535 - POSITION)-(TMR1H*256))    'EXTRACT LOW BYTE
        HSEROUT ["HIGH: ", DEC TMR1H," LOW: ", DEC TMR1L,10]
        SERVO1 = 1
        HSEROUT ["SERVO1: ",DEC SERVO1,10,10]
    ENDIF
    
    IF SERVO1 = 1 THEN
        HSEROUT ["SECOND IF - TMROFF: ",DEC TMROFF,10]
        TMR1H = ((65535 - TMROFF)/256)              'EXTRACT HIGH BYTE INTO TIMER1
        TMR1L = ((65535 - TMROFF)-(TMR1H*256))      'EXTRACT LOW BYTE
        HSEROUT ["HIGH: ", DEC TMR1H," LOW: ", DEC TMR1L,10,10,13]
        SERVO1 = 0
        HSEROUT ["SERVO1: ",DEC SERVO1,10,10]
    ENDIF
    INTCON.0 = 0
    PIR1.0 = 0
RESUME
ENABLE' INTERRUPT

and here's the results on the serial port:

FIRST IF - POSITION: 225
HIGH: 12 LOW: 64
SERVO1: 0

This is where it gets weird. I'm trying to extract the high and low bits for timer1, ie. I want the timer to countdown for the amount of time stored in 'position'. So the timer has to equal 65535 - Position. I need to break this down into the high and low bits for tmr1H and tmr1L. So tmr1H = 65535 - position / 256 etc. (much thanks to Aratti for helping me with that).

The strange thing is the value that the PIC has calculated for high and low.

high should equal (65535 - 225(value for position is shown in serout))/256 = 255.11 (I know we'll lose the .11)

Low should equal ((65535 - 225)-(255*256) = 30
of course this last value won't be correct until the first one comes out right, but even with the first incorrect value from formula one in place it's still all wrong.

I can't figure it out. Why so far out?
It looks too simple to go wrong. I'm missing something.

Can hair be glued back in?

I can't find a smilie for crying desperately...

[bison_bloke]

Hey Ace, thanks for looking it over.

As mentioned briefly above, when I cut and pasted my code, it seems a lot of the symbols didn't come across. I'll repost here:

define OSC 4
ON INTERRUPT GOTO INTCODE


DEFINE HSER_TXSTA 20h       'SET THE TRANSMIT REGISTER TO TRANSMITTER ENABLED
DEFINE HSER_BAUD 2400       'SET BAUD RATE
                            'DEFINE ADCIN PARAMETERS
Define ADC_BITS	10          'SET NUMBER OF BITS IN RESULT
Define ADC_CLOCK 3          'SET CLOCK SOURCE (3=RC)
Define ADC_SAMPLEUS 50	    'SET SAMPLEING TIME IN uS
define LOADER_USED 1

SELECTOR    VAR BYTE        'SELECTS PROGRAM TYPE
TEMP        VAR WORD        'TEMPORY VARIABLE FOR ANY USE
POSITION    VAR WORD        'POSITION OF SERVO1 1250 - 2500
OFFWIDTH    VAR WORD        'HOW LONG THE PULSE NEEDS TO BE OFF FOR
FREQ        VAR WORD        'FREQUENCY TO RUN THE SERVOS AT
PICOSC      VAR BYTE BANK0  'TO STORE OSCILLATOR FREQUENCY IN
PERIOD      VAR WORD        'TEMPORY VARIABLE TO DISPLAY THE PERIOD OF PULSE
PRESCALER   VAR WORD        'STORES THE TIMER1 PRESCALER VALUE
TMROFF      VAR WORD        'STORES THE TIME THAT THE SERVO1 PULSE WILL BE LOW
RUN         VAR BIT         'IS THE PROGRAM RUNNING?

ADCON1 = %10000010          'SET PORTA ANALOGUE AND RIGHT JUSTIFY THE RESULT

SERVO1      var PORTA.0     'OUTPUT PIN FOR SERVO1
PUSHBUTT    VAR PORTA.2     'INPUT PIN FOR PUSHBUTTON
TRISB.4 = 1                 'INPUT FOR SELECTOR SWITCH PIN 13
TRISA.0 = 0                 'MAKES PIN 19 AN OUTPUT FOR SERVO1
TRISA.2 = 1                 'MAKES PIN 17 AN INPUT FOR PUSHBUTTON

PRESCALER = 8               'DEFINES THE TIMER1 PRESCALER AS 1:8
FREQ = 50                   'CONSTANT FREQUENCY FOR THE SERVOS
RUN = 0                     'TEMPORARY VARIABLE FOR SERVO RUNNING

T1CON  = %00110001          'ENABLE X,X,PRESCALER = 8,X,X,X,TMR1ON 
INTCON     = %11001000      'ENABLE GIE,PEIE,x,x,GPIE,x,x,x
GIE         var INTCON.7
PEIE        var INTCON.6
TMR1IE      var PIE1.0
TMR1ON      var T1CON.0
TMR1IE = 1                  '
PEIE = 1                    'WHO KNOWS
GIE = 1                     'WHAT ALL OF 
PIR1.0 = 0                  'THESE DO, BUT IT 
TMR1H = 0                   'DIDN'T START 
TMR1L = 0                   'WITHOUT THEM.

GOSUB GETOSC 

MAINLOOP:
        IF PUSHBUTT = 1 THEN 
            HSEROUT ["HIGH.",13,10]
        ELSE 
            HSEROUT ["LOW",13,10]
        ENDIF
        GOSUB FINDPROGRAM
        GOSUB STARTPULSE
        'GOSUB STOPPULSE
GOTO MAINLOOP

FINDPROGRAM:                'SELECTS BETWEEN SEVERAL TYPES OF MOTION
    ADCIN 10, TEMP          'READ CHANNEL 10 TO TEMP
    IF TEMP <= 15000 THEN POSITION = 125                    'USES VOLTAGE DIVIDER TO
    IF TEMP > 15000 AND TEMP <= 22000 THEN POSITION = 150   'VARY THE VOLTAGE ON CH10.
    IF TEMP > 22000 AND TEMP <= 35000 THEN POSITION = 175   'THIS CONVERTS AND STORES
    IF TEMP > 35000 AND TEMP <= 47000 THEN POSITION = 200   'TO 'TEMP'.
    IF TEMP > 47000 AND TEMP <= 60000 THEN POSITION = 225   
    IF TEMP > 60000 THEN POSITION = 250
    GOSUB SETPULSE   
RETURN

DISABLE' INTERRUPT
INTCODE:
    IF SERVO1 = 0 THEN
        HSEROUT ["FIRST IF - POSITION: ",DEC POSITION,10]
        TMR1H = ((65535 - POSITION)/256)            'EXTRACT HIGH BYTE INTO TIMER1
        TMR1L = ((65535 - POSITION)-(TMR1H*256))    'EXTRACT LOW BYTE
        HSEROUT ["HIGH: ", DEC TMR1H," LOW: ", DEC TMR1L,10]
        SERVO1 = 1
        HSEROUT ["SERVO1: ",DEC SERVO1,10,10]
    ENDIF
    
    IF SERVO1 = 1 THEN
        HSEROUT ["SECOND IF - TMROFF: ",DEC TMROFF,10]
        TMR1H = ((65535 - TMROFF)/256)              'EXTRACT HIGH BYTE INTO TIMER1
        TMR1L = ((65535 - TMROFF)-(TMR1H*256))      'EXTRACT LOW BYTE
        HSEROUT ["HIGH: ", DEC TMR1H," LOW: ", DEC TMR1L,10,10,13]
        SERVO1 = 0
        HSEROUT ["SERVO1: ",DEC SERVO1,10,10]
    ENDIF
    INTCON.0 = 0
    PIR1.0 = 0
RESUME
ENABLE' INTERRUPT

SETPULSE:
    POSITION = POSITION MIN 250  'MIN POSITION LIMITED TO 0 DEGREES
    POSITION = POSITION MAX 125  'MAX POSITION LIMITED TO 180 DEGREES
    HSEROUT ["POSITION = ",DEC POSITION,10,13]
    TMROFF = (((((10000 / FREQ) * 10) / PRESCALER)*10) - POSITION)
    'HSEROUT ["TMROFF = ",DEC TMROFF,10,10]
    'PERIOD = TMROFF + POSITION
    'HSEROUT ["PERIOD = ",DEC PERIOD,10,10]
    
RETURN

STARTPULSE:
    HSEROUT ["PULSE STARTED",10,10]
    LOW SERVO1
    'GIE = 1             'GLOBAL INTERRUPT ENABLE
    'PEIE = 1            'PERIPHRIAL INTERRUPT ENABLE
    TMR1H = 255         'SETS TIMER1 TO 65535 
    TMR1L = 255         'NEXT TICK WILL INTERRUPT
    TMR1ON = 1
RETURN

STOPPULSE:
    HSEROUT ["PULSE STOPPED",10,10]
    LOW SERVO1
    PEIE =0
RETURN

GETOSC:

asm
    ifdef OSC
       MOVE?CB   OSC, _PICOSC
    else
       MOVE?CB   4, _PICOSC
    endif
endasm
RETURN

END

I hope it worked this time, dunno what went wrong the first time.