Hi all,
I am using CCS v 6.1 and with TM4C123G development Board. Recently I wrote down a code to toggle LED at every 1 Sec with systick. It was working fine, then for some reason I had to reset my PC and had to reinstall CCS . I also updated CCS after installation.
Now the problem is, with the same program LED is toggling on every 3 sec rather than one sec. I tried with other timer modules as well by loading timer with “SysCtlClockGet() -1” and getting the same results. Is my assumption is right that CCS is doing something wrong?
Below is the code.
------------------------------------------------
#include <stdio.h>
#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_memmap.h"
#include "driverlib/gpio.h"
#include "driverlib/interrupt.h"
#include "driverlib/pin_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/systick.h"
#include "driverlib/uart.h"
//*****************************************************************************
// Counter to count the number of interrupts that have been called.
//*****************************************************************************
volatile uint32_t g_ui32Counter = 0;
//*****************************************************************************
// The interrupt handler for the for Systick interrupt.
//*****************************************************************************
void SysTickIntHandler(void)
{
g_ui32Counter++;
}
//*****************************************************************************
// Configure the SysTick and SysTick interrupt with a period of 1 second.
//*****************************************************************************
int main(void)
{
// Set the clocking to run directly from the external crystal/oscillator.
SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOG);
GPIOPinTypeGPIOOutput(GPIO_PORTG_BASE, GPIO_PIN_2);
// Set up the period for the SysTick timer. The SysTick timer period will
// be equal to the system clock, resulting in a period of 1 second.
SysTickPeriodSet(SysCtlClockGet());
// Enable interrupts to the processor.
IntMasterEnable();
// Enable the SysTick Interrupt.
//
SysTickIntEnable();
// Enable SysTick.
//
SysTickEnable();
//
// Loop forever while the SysTick runs.
//
while(1)
{
if(g_ui32Counter >= 3)
{
// Read the current state of the GPIO pin and
// write back the opposite state
if(GPIOPinRead(GPIO_PORTG_BASE, GPIO_PIN_2))
{
GPIOPinWrite(GPIO_PORTG_BASE, GPIO_PIN_2, 0);
}
else
{
GPIOPinWrite(GPIO_PORTG_BASE, GPIO_PIN_2, 4);
}
g_ui32Counter = 0;
}
}
}
