TMR2 not working..

[Darrel Taylor]

The default LCD_COMMANDUS is 2000 us. (2 ms)
So moving the cursor to a specific location within the ISR makes it wait that much longer before it Resume's.

Add in the 50us for each character displayed, and the 1ms for the interrupt itself, and you get "3ms or something...".

HTH,

[sirvo]

Right.. i just put the LCDOUT command to compare the count with my hand watch. So, the routine is correct.. thanks Darrel.

Sylvio

[Darrel Taylor]

... So, the routine is correct..

Good to go ...
One thing to note ...
You don't need to reload PR2 each time. It doesn't change.
<br>

[sirvo]

0.o I've read that a thousand times and still reloaded..Thanks again..

Sylvio

[sirvo]

HI Again... I have tried again taking the LCDOUT command out of interrupt routine and putting inside the MAIN sub. NOthing! It is running crazy and I've also tried setting postscaler 1:16 or/and prescaler 1:16 and still nothing. Does the code look really correct? What I want is to set any flag every 500ms using TMR2... A little help please?

Thanks again.. Sylvio,

'------- initial -------------------- 
TMR2_clock   VAR   WORD
OPTION_REG = %00000000 
INTCON 	= %11000000 ' enable interrupts
TRISB = %00000000 ' portb all output
TRISA = %00111111 ' some analog inputs
ANSEL = %00001111 ' some analog inputs
CMCON = %00000111 ' turn of comparators
ADCON1 = %10000000' right justified
T2CON = %00000011 ' TMR2 prescale 1:16 --> TESTED WITH POST and PRESCALER (1:16)
'--------------------------------------------------- 
TMR2_clock = 0
    
    
    Lcdout $FE,1 ' clear screen
    
    PR2 = 194 ' load tmr2 PR2 to reset every 1ms
    PIE1.1 = 1 ' enable TMR2 interrupt
    PIR1.1 = 0 ' disabled interrupt flag - TMR2
    T2CON.2 = 1 ' turn TMR2 on

    ON INTERRUPT GOTO tick

MAIN:
    Lcdout $FE,$A0, DEC TMR2_clock ---> CHANGED
GOTO MAIN

    DISABLE      
tick:
    TMR2_clock = TMR2_clock + 1
    IF TMR2_clock = 500 THEN 
         TMR2_clock = 0
         ' Set some flag..
    ENDIF
    PIR1.1 = 0
resume
    ENABLE

[Darrel Taylor]

You've just moved the time to write to the LCD to a different place.

When using ON INTERRUPT, it can't handle an interrupt until the current statement has finshed executing.

If you want to have a 1ms interrupt, then nothing else in the program can take more than 1ms to execute, and really should be much less than that.

If you were using ASM interrupts, then it could interrupt the LCDOUT statement, so there wouldn't be a conflict.

Or you could use Instant Interrupts to do the same thing with Basic language interrupts without the ON INTERRUPT.
<br>

[sirvo]

OK. Let's try the instant interrupts. I have just added the II codes and it looks like this:

@ ERRORLEVEL -306   ; turn off crossing page boundary message
@  __CONFIG    _CONFIG1, _CP_OFF  & _DEBUG_OFF & _WRT_PROTECT_OFF & _CPD_OFF & _LVP_OFF & _BODEN_OFF & _MCLR_OFF & _PWRTE_ON & _WDT_OFF & _XT_OSC

INCLUDE "DT_INTS-14.bas"     ' Base Interrupt System
INCLUDE "ReEnterPBP.bas"     ' Include if using PBP interrupts

ASM
;T0IF = TMR0IF
;T0IE = TMR0IE
INT_LIST  macro    ; IntSource,        Label,  Type, ResetFlag?
        INT_Handler   TMR2_INT,  _tick,   PBP,  yes
    endm
    INT_CREATE               ; Creates the interrupt processor
ENDASM
@    INT_ENABLE  TMR2_INT     ; Enable Timer 1 Interrupts  

'------- initial -------------------- 
TMR2_clock   VAR   WORD
OPTION_REG = %00000000 
' INTCON 	= %11000000 ' enable interrupts ->NOW COMMENTED
TRISB = %00000000 ' portb all output
TRISA = %00111111 ' some analog inputs
ANSEL = %00001111 ' some analog inputs
CMCON = %00000111 ' turn of comparators
ADCON1 = %10000000' right justified
T2CON = %00000011 ' TMR2 prescale 1:16 --> TESTED WITH POST and PRESCALER (1:16)
'--------------------------------------------------- 
TMR2_clock = 0
    
    
    Lcdout $FE,1 ' clear screen
    
    PR2 = 194 ' load tmr2 PR2 to reset every 1ms
    'PIE1.1 = 1 ' enable TMR2 interrupt -> NOW COMMENTED
    'PIR1.1 = 0 ' disabled interrupt flag - TMR2 -> NOW COMMENTED
    T2CON.2 = 1 ' turn TMR2 on

    'ON INTERRUPT GOTO tick -> -> NOW COMMENTED

MAIN:
    Lcdout $FE,$A0, DEC TMR2_clock ---> CHANGED
GOTO MAIN

   
tick:
    TMR2_clock = TMR2_clock + 1
    IF TMR2_clock = 500 THEN 
         TMR2_clock = 0
         ' Set some flag..
    ENDIF
@ INT_RETURN

Well.. the LCD gets cleared. No text at all..

What's wrong?

Thank you.

Sylvio