4.24.1.2 8/16-bit TMR0

• Add Timer0 (or another timer) to the project

• Configure:

  1. TimerX as described in the example.

  2. Any other peripherals or pins needed for the use case.

• Generate the code

• Add the code snippet(s) to the application code

• Program the board

• Note: The main clock is asumed to use the HFINTOSC (High Frequency Internal Oscillator) as a clock source. In these use cases the Timer is configured to run asynchronously from the main clock, using the LFINTOSC (Low Frequency Internal Oscillator).

• Timer > Hardware Settings:

  1. Clock Source set to LFINTOSC //Low Frequency Internal Oscillator

  2. Clock Prescaler 1:16

  3. Requested Period(s): 0.1(s).

• Timer > Interrupt Settings:

  1. TMR Interrupt: Yes.

• System > Pins (for all pins check board schematics):

  1. Pin Grid View: Select LED pin, DebugIO pin as outputs (Check board schematic).

  2. Pins: Rename Custom Names to "LED" and "DebugIO", respectively.  

#include "mcc_generated_files/system/system.h"  

/* Create a pointer of type TMR_INTERFACE and assign it to the address of the Timer0 TMR_INTERFACE struct.
This enables us to get access the portable API interface, which ensures that it's easy to change the peripheral instance the timer runs on. */
const struct TMR_INTERFACE *Timer = &Timer0; 

void Timer_Callback_100ms(void){
    LED_Toggle();
    DebugIO_Toggle();
}

int main(void)
{
    SYSTEM_Initialize();
    Timer->TimeoutCallbackRegister(Timer_Callback_100ms);

    INTERRUPT_GlobalInterruptEnable(); 

    while(1){}    
}

• Timer > Hardware Settings:

  1. Clock Source set to LFINTOSC //Low Frequency Internal Oscillator

  2. Clock Prescaler 1:1 //Default

  3. Timer Mode: 16-bit

  4. Requested Period(s): 0.1(s).

• Timer > Interrupt Settings:

  1. TMR Interrupt: Yes.

• System > Pins (for all pins check board schematics):

  1. Pin Grid View: Select LED pin as output  

  2. Pins: Rename Custom Name to "LED".  

  3. SWITCH pin as INPUT, name it "SW".  

  4. Enable Weak Pullup if needed  

  5. Interrupt on Change: Sense negative/positive on switch press  

#include "mcc_generated_files/system/system.h"

/* Create a pointer of type TMR_INTERFACE and assign it to the address of the Timer0 TMR_INTERFACE struct.
This enables us to get access the portable API interface, which ensures that it's easy to change the peripheral instance the timer runs on. */
const struct TMR_INTERFACE *Timer = &Timer0;

#define LED_100ms (0xF3E4)
#define LED_500ms (0xC374)
volatile bool CHANGE_PERIOD = false;
volatile bool PERIOD_100ms = true;  /*Global variable to check the current period value*/

void Timer_Callback(void)
{
    LED_Toggle();
}

void SW_Callback(void)
{
    CHANGE_PERIOD = true;
}

void Timer_Change_Frequency(void){
    Timer->Stop();
    if(PERIOD_100ms)
    {
        TMR0 = 0x0;   //Restart the timer
        Timer->PeriodCountSet(LED_500ms);
        PERIOD_100ms = false;
    }
    else
    {
        TMR0 = 0x0;   //Restart the timer
        Timer->PeriodCountSet(LED_100ms);
        PERIOD_100ms = true;
    }
    Timer->Start();
}

int main(void)
{
    SYSTEM_Initialize();
    Timer->TimeoutCallbackRegister(Timer_Callback);
    RC0_SetInterruptHandler(SW_Callback);             /* Select for SW pin you are using */
    
    INTERRUPT_GlobalInterruptEnable();
    
    while(1)
    {
        if(CHANGE_PERIOD)
        {
            Timer_Change_Frequency();
            __delay_ms(100);    //De-bounce delay
            CHANGE_PERIOD = false;
        }
    }
}

• Timer > Hardware Settings:

  1. Clock Prescaler: 1:32 (or greater)

  2. Timer Mode: 16-bit

  3. Clock Source set to LFINTOSC //Low Frequency Internal Oscillator

  4. Requested Period(s): 10 seconds

• Timer > Interrupt Settings:

  1. TMR Interrupt: Yes. //No callback, only used to wake MCU from sleep.

• System > Pins (for all pins check board schematics):

  1. Pin Grid View: Select LED pin, DebugIO pins as outputs.

  2. Pins: Rename Custom Names to "LED" and "DebugIO", respectively.  

#include "mcc_generated_files/system/system.h"

int main(void)
{
    SYSTEM_Initialize();

    // Enable the Global Interrupts
    INTERRUPT_GlobalInterruptEnable();

    while(1){
        LED_SetLow();     //Set LED High
        DebugIO_SetLow();
        __delay_ms(100);  //100ms Delay in between LED toggle
        LED_SetHigh();    //Set LED Low
        DebugIO_SetHigh();
        SLEEP();          //Put microcontroller in Sleep
    }
}

• Timer > Hardware Settings:

  1. Clock Source set to LFINTOSC. //Low Frequency Internal Oscillator

  2. Set Requested Period(s) to 0.004 seconds.

• System > Pins (for all pins check board schematics):

  1. Pin Grid View > TMR0 Output: Select GPIO to use as CLK_OUT pin

#include "mcc_generated_files/system/system.h"

int main(void)
{
    SYSTEM_Initialize();

    while(1){}
}