[PIC] PIC18F4550 USB Frequency Counter Interrupt Problem

[Astralist]

Hi, i'm currently building a frequency counter and also to plot adc graph using PIC18F4550
im using software on computer as a user interface.

right now i'm having problem in interrupt routines. it seems not firing.
this is my first time using timer and interrupt routine.

i've searched through the web, and datasheet. seems i'm still missing some config here.

please check my code, im using HI-Tech PIC18 9.63 PL2 on MPLAB 8.83 IDE.
XTAL freq = 20MHz, set to 48MHz by PLL for USB operation.

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Code C - [expand]
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#ifndef MAIN_C
#define MAIN_C
 
#include <htc.h>
#include "usb.h"
#include "HardwareProfile.h"
#include "usb_function_hid.h"
#include "genericHID.h"
 
__CONFIG(1, USBPLL & IESODIS & FCMDIS & HSPLL & CPUDIV1 & PLLDIV5);
__CONFIG(2, VREGEN & PWRTDIS & BOREN & BORV20 & WDTDIS & WDTPS32K);
__CONFIG(3, PBDIGITAL & LPT1DIS & MCLREN);
__CONFIG(4, XINSTDIS & STVREN & LVPDIS & ICPORTDIS & DEBUGDIS);
__CONFIG(5, UNPROTECT);
__CONFIG(6, UNPROTECT);
__CONFIG(7, UNPROTECT);
 
void InitialiseSystem();
void ProcessIO();
void SendPacket();
void SetADCON12_VddVref();
void SetADCON12_ExtVref();
void start_timer_count();
void interrupt ISR();
short do_TMR0_end_count = 0;
short FreqRdy = 0;
short toggle_LED = 0;
unsigned long TMR1_counter = 0;  
unsigned long TMR0_counter = 0;  
unsigned short st_TMR1L       ; 
unsigned short st_TMR1H       ; 
unsigned long  st_TMR1_ovfl = 0 ; 
 
void main(void)
{
    InitialiseSystem();
    start_timer_count();
    while(1)
    {
        USBDeviceTasks();
        if (FreqRdy == 1) 
        {       
            GIE = 0;         
            PEIE = 0;                   
        }                               
        if (toggle_LED == 1)
        { 
            //RC7 != RC7;
            toggle_LED = 0;
        }       
        ProcessIO();        
    }
}
 
void start_timer_count() 
{
   GIE = 0;         
   PEIE = 0;        
   TMR1H = 0;              
   TMR1IF = 0;  
   TMR1L = 0;              
   TMR1_counter = 0;   
   TMR0 = 0;               
   T1CON = 0b00000111;
   PSA = 1;
   TMR0IF = 0;     
   TMR0IE = 1;    
   TMR1IF = 0;
   TMR1IE = 1;
   TMR0ON = 1;  
   GIE = 1;         
   PEIE = 1;        
}
 
void interrupt counter() 
{
   RC7 = 1; //to check if interrupt is firing
   if (TMR1IF == 1)
   {
       TMR1_counter++;
       TMR1IF = 0;
   }
   if (TMR0IF == 1)
   {
        TMR0_counter++;
        if(do_TMR0_end_count) 
        { 
            st_TMR1L = TMR1L; 
            st_TMR1H = TMR1H;
            st_TMR1_ovfl = TMR1_counter;
            TMR1_counter = 0;
            TMR0_counter = 0;
            FreqRdy = 1;     
            do_TMR0_end_count = 0;
        } 
        else 
        {
            if(TMR0_counter == 46875) 
            { 
                do_TMR0_end_count = 1;
                toggle_LED = 1;
            }
        }
    TMR0IF = 0;
   } 
}
 
void InitialiseSystem()
{
    TRISA = 0b00001111;
    TRISB = 0b00000000;
    TRISC = 0b00000011;
    TRISD = 0b00000000;
    TRISE = 0b0000;
    PORTA = 0b00000000;    
    PORTB = 0b00000000;
    PORTC = 0b00000000;
    PORTD = 0b00000000;
    PORTE = 0b0000;
    UPUEN = 1;
    FSEN = 1;
    USBOutHandle = 0;
    USBInHandle = 0;
    USBDeviceInit();
}
 
void SendPacket()
{
    if(!HIDTxHandleBusy(USBInHandle))
    {
        USBInHandle = HIDTxPacket(HID_EP,(BYTE*)&ToSendDataBuffer[0],64);
    }
}
 
void SetADCON12_VddVref()
{
    ADCON1 = 0b00001011;
    ADCON2 = 0b10001110;
}
 
void SetADCON12_ExtVref()
{
    ADCON1 = 0b00011011;
    ADCON2 = 0b10001110;
}
 
void ProcessIO()
{   
    if((USBDeviceState < CONFIGURED_STATE)||(USBSuspendControl == 1)) return;
    if(!HIDRxHandleBusy(USBOutHandle))
    {   
        switch(ReceivedDataBuffer[0])
        {
            case 1:
                if (FreqRdy)
                {                   
                    ToSendDataBuffer[0] = 1;
                    ToSendDataBuffer[1] = st_TMR1L;
                    ToSendDataBuffer[2] = st_TMR1H;
                    ToSendDataBuffer[3] = st_TMR1_ovfl;
                    SendPacket();
                    FreqRdy = 0;        
                    start_timer_count();
                }
                else
                {
                    ToSendDataBuffer[0] = 1;
                    ToSendDataBuffer[1] = 0;
                    ToSendDataBuffer[2] = 0;
                    ToSendDataBuffer[3] = 0;
                    SendPacket();
                }
                break;
            case 2:
                SendPacket();
                break;
        }
        USBOutHandle = HIDRxPacket(HID_EP,(BYTE*)&ReceivedDataBuffer,64);
    }  
}
#endif

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[dhakeparag81]

I don't understand, will you plz elaborate your problem.

 

[Astralist]

actually, this is still in simulation (using ISIS Proteus)

my attempt to count frequency:
i'm using Timer0 and Timer1
Timer0 for counting period of 1sec.
Timer1 for counting transition on RC0/T1CKI
when Timer0 reach overflow 46875x (1sec), then RC7 (LED) should turned on.
but as RC7 (LED) never turned on, then i checked the interrupt routine.

to make a proof if interrupt being called by adding RC7 = 1; on interrupt routine
look at line 77, basically when interrupt occur, the led will turned on.
but as the RC7 not become high, so i assume that the interrupt routine are not being called.

because of this, my attempt to calculate frequency was failed.

p.s: the connection to TICK1 seems fine, and the input are sine wave.

 

[FvM]

Proteus µC debug features are limited, but at least allow you to check if the code is continuously executing, if SFR and variables have the expected state. Did you try?

By loading a *.cof instead of a *.hex file, you enable source level debugging.