tmr2 interrupt problem

[ADCON]

Hello all,

I have a problem with a tmr2interrupt. I have programmed a several things but that was lways in loops and now 1 want to change my program.

I use a pic16f628 controller at 4MHz internal ascillator.
I want to use timer2 to generate an interrupt every 2milliseconds.
Only problem is that it never gets to the interruptroutine..
It is for a RTC controlled clock with muxed 7segment displays at two 74hc595 shiftregisters.

Here is the problem code

@ DEVICE pic16F628a, INTRC_OSC_NOCLKOUT
' System Clock Options
@ DEVICE pic16F628a, WDT_OFF
' Watchdog Timer
@ DEVICE pic16F628a, PWRT_ON
' Power-On Timer
@ DEVICE pic16F628a, BOD_ON
' Brown-Out Detect
@ DEVICE pic16F628a, MCLR_OFF
' Master Clear Options (Internal)
@ DEVICE pic16F628a, LVP_OFF
' Low-Voltage Programming
@ DEVICE pic16F628a, CPD_OFF
' Data Memory Code Protect
@ DEVICE pic16F628a, PROTECT_OFF
' Program Code Protection
@ DEVICE pic16F628a, MCLR_OFF
define OSC 4 'runs at 4MHz

INCLUDE "modedefs.bas" 'for shiftout

segments var byte
counter var byte

Symbol tmr2if=PIR1.1
Symbol tmr2ie=PIE1.1
Symbol gie =INTCON.7

'Turn on INTCON.7(GIE) and INTCON.5 (TMR0IE)
INTCON = %10100000
tmr2ie=1
gie=1

on interrupt GoTo isr
GoTo loop

;-----------------------------------------------------------
isr:
'Clear tmr2if
disable
segments = %01111011
counter=%00000000 'only for test. all segments are on.
if hr.6=1 then 'mode indication
segments.7=%1
endif
SHIFTOUT PORTB.0, PORTB.1, LSBFIRST,[counter\8,segments\8] 'data, clock
pulsout PORTA.4,1
'return
INTCON.6 =0
enable
INTCON.6 =0
resume

loop: 'main programloop
repeat
'sec=%00000111
until 0=1
END

The full code is about 10 a4 sides of paper..

I hope that anyone knows what I do wrong and can help me.

Thanks.
Martijn

[mister_e]

almost sure i'm right, you should enable peripheral interrupts as well. INTCON.6=1

mmm, Tmier2---shouldn't be something to do with PR2 as well?

i'll dig the datasheet.. been awhile i didn't use that pic now.

[ADCON]

Thnx for the fast answere.

Wel, i only make intcon.6 0 in the isr-loop.

Hope you can help me..

[mister_e]

TRY

        @ __CONFIG  _INTRC_OSC_NOCLKOUT & _MCLRE_ON  &  _LVP_OFF & _WDT_OFF & _PWRTE_ON  & _BODEN_ON  

        CMCON=7
        TRISA=0
        TRISB=0
        PORTA=0
        PORTB=0
      
        PIE1 =  %00000010
                '0------- Disable EE write complete interrupt
                '-0------ Disable comparator interrupt
                '--0----- Disable USART receive interrupt
                '---0---- Disable USART transmit interrupt
                '----x--- unimplemented
                '-----0-- Disable CCP1 interrupt
                '------1- Enable TMR2 to PR2 match interrupt
                '-------0 Disable TMR1 overflow interrupt
                
        T2CON = %00000010
                'X------- Unimplemented
                '-0000--- postscale 1:1
                '-----0-- Timer2 off
                '------10 prescaler 1:16
                
                        
        GIE     VAR INTCON.7
        PEIE    VAR INTCON.6
        TMR2IF  VAR PIR1.1
        TMR2ON  VAR T2CON.2
        RELOAD CON 131
        
        ON INTERRUPT GOTO ISR
        TMR2 = RELOAD
        PR2 = 0
        PEIE = 1    ' Enable peripheral interupt
        GIE = 1     ' enable Global interrupt
        TMR2ON = 1  ' TMR2 ON
        GOTO LOOP                

        disable
ISR:
        TOGGLE PORTB.0
        TMR2ON = 0
        TMR2 = RELOAD
        TMR2ON = 1
        TMR2IF = 0  ' Clear interrupt flag
        resume
        enable
        
LOOP:
        'TOGGLE PORTB.1
        GOTO LOOP

or another variant of

        @ __CONFIG  _INTRC_OSC_NOCLKOUT & _MCLRE_ON  &  _LVP_OFF & _WDT_OFF & _PWRTE_ON  & _BODEN_ON  

        CMCON=7
        TRISA=0
        TRISB=0
        PORTA=0
        PORTB=0
      
        PIE1 =  %00000010
                '0------- Disable EE write complete interrupt
                '-0------ Disable comparator interrupt
                '--0----- Disable USART receive interrupt
                '---0---- Disable USART transmit interrupt
                '----x--- unimplemented
                '-----0-- Disable CCP1 interrupt
                '------1- Enable TMR2 to PR2 match interrupt
                '-------0 Disable TMR1 overflow interrupt
                
        T2CON = %00000010
                'X------- Unimplemented
                '-0000--- postscale 1:1
                '-----0-- Timer2 off
                '------10 prescaler 1:16
                
                        
        GIE     VAR INTCON.7
        PEIE    VAR INTCON.6
        TMR2IF  VAR PIR1.1
        TMR2ON  VAR T2CON.2
        
        ON INTERRUPT GOTO ISR
        PR2 = 124   ' load period register for 2mSec 
        PEIE = 1    ' Enable peripheral interupt
        GIE = 1     ' enable Global interrupt
        TMR2ON = 1  ' TMR2 ON
        GOTO LOOP                

        disable
ISR:
        TOGGLE PORTB.0
        TMR2IF = 0  ' Clear interrupt flag
        resume
        enable
        
LOOP:
        'TOGGLE PORTB.1
        GOTO LOOP

The second one is probably the best method to deal with Timer2. have a look to section 6.0 of your datasheet.

[ADCON]

Thanks, it works now!
First i tried to inplement your code in mine but that didnd work.
So I fit my program in yours and the first test works.
Here's my code fore enyone with the same problem.
Now I'm have to set all my other code in it. Hope it don't make problems with the changed config now.

 @ device pic16F628a, INTRC_OSC_NOCLKOUT
 @ device pic16F628a, MCLR_ON
 @ device pic16F628a, LVP_OFF
 @ device pic16F628a, WDT_OFF
 @ device pic16F628a, PWRT_ON
 @ device pic16F628a, BOD_ON   
INCLUDE "modedefs.bas"  'for shiftout
 
        CMCON=7
        TRISA=0
        TRISB=0
        PORTA=0
        PORTB=0
      
        PIE1 =  %00000010
                '0------- Disable EE write complete interrupt
                '-0------ Disable comparator interrupt
                '--0----- Disable USART receive interrupt
                '---0---- Disable USART transmit interrupt
                '----x--- unimplemented
                '-----0-- Disable CCP1 interrupt
                '------1- Enable TMR2 to PR2 match interrupt
                '-------0 Disable TMR1 overflow interrupt
                
        T2CON = %00000010
                'X------- Unimplemented
                '-0000--- postscale 1:1
                '-----0-- Timer2 off
                '------10 prescaler 1:16
                
        segments var byte
        counter var byte                
        GIE     VAR INTCON.7
        PEIE    VAR INTCON.6
        TMR2IF  VAR PIR1.1
        TMR2ON  VAR T2CON.2
        
        ON INTERRUPT GOTO ISR
        PR2 = 124   ' load period register for 2mSec 
        PEIE = 1    ' Enable peripheral interupt
        GIE = 1     ' enable Global interrupt
        TMR2ON = 1  ' TMR2 ON
        GOTO LOOP                

        disable
ISR:
'first half of the displays
segments=%01011011 '5
counter=%01010101  'on displays
SHIFTOUT PORTB.0, PORTB.1, LSBFIRST,[counter\8,segments\8]   'data, clock
pulsout PORTA.4,1 'for latch 74hc595
 
'remaining displays  
segments = %00110000 '1
counter=%10101010
SHIFTOUT PORTB.0, PORTB.1, LSBFIRST,[counter\8,segments\8]   'data, clock
pulsout PORTA.4,1 'for latch 74hc595
'------- ^^my try
 
        TOGGLE PORTB.0
        TMR2IF = 0  ' Clear interrupt flag
        resume
        enable
        
LOOP:
        'TOGGLE PORTB.1
        GOTO LOOP
end

[ADCON]

Dear,

I still have a problem.

I have merged all the code and the beginning works fine now.
It go's to the loop: makes a I2C read.
Go's to another loop for I2C write(only if needed).

Then it have to wait for the the interupt.
At the interrupt is starts to shiftout the data for the display.
Until here it works fine.

The problem is: it keeps doing that and NEVER goes back to the loop..

This didn't I know becose in the testprogram there was noting to do in the loop..

I can post the code when someone needs it but it's the same as above, only with some onther code inside it.

Dos anyone know what I do wrong?