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TM4C123GH6PM: Change PWM pins in EK_TM4C123GXL.c?

Part Number: TM4C123GH6PM


Just a quick question: Will I run into any problems changing the pwm pins in the EK_TM4C123GXL.c file? I need these pins for a capture/compare. Thank you. 

/*
 *  ======== EK_TM4C123GXL_initPWM ========
 */
void EK_TM4C123GXL_initPWM(void)
{
    /* Enable PWM peripherals */
    SysCtlPeripheralEnable(SYSCTL_PERIPH_PWM1);

    /*
     * Enable PWM output on GPIO pins.  Board_LED1 and Board_LED2 are now
     * controlled by PWM peripheral - Do not use GPIO APIs.
     */
    GPIOPinConfigure(GPIO_PF2_M1PWM6);
    GPIOPinConfigure(GPIO_PF3_M1PWM7);
    GPIOPinTypePWM(GPIO_PORTF_BASE, GPIO_PIN_2 |GPIO_PIN_3);

    PWM_init();
}

  • The schematic for the EK_TM4C123GXL is in appendix A of the User's Guide. The first page of the schematic (document page 20) shows both PF2 and PF3 controlling the RGB LED through the biased transistors DTC114EET1G. The resistor to the base is a minimum of 7K Ohms. Driving these signals externally will turn on the RGB LED. The 330 Ohm resistor limits the current. The most sensitive part of the LED is the blue LED. It has a maximum steady state forward current of 10mA and a minimum forward voltage of 2.60 V. The 330 Ohm resistor limits the forward current to 7.2 mA. It should be no problem if you don't mind the RGB LED turning on.