How to use the GTM TOM PWM Driver

Collaboration diagram for How to use the GTM TOM PWM Driver:

This interface allows to generate simple PWM signal on a TOM out put and can generate interrupts if enabled. this output can also be routed to port pin if required.

Preparation

Include Files

Include following header file into your C code:

#include <Gtm/Tom/Pwm/IfxGtm_Tom_Pwm.h>

Variables

define global variables if necessary

Ifx_GTM *gtm = &MODULE_GTM;
#define TOM0_CH0_PRIO 10

Interrupts

define Interrupts if needed

IFX_INTERRUPT(TOM0Ch0_ISR, 0, TOM0_CH0_PRIO)
{}

Initialization

// install interrupt handlers
IfxCpu_Irq_installInterruptHandler (TOM0Ch0_ISR, TOM0_CH0_PRIO);

// enable GTM clock
{
    float32 frequency = IfxGtm_Cmu_getModuleFrequency(gtm);
    // Enables the GTM
    IfxGtm_enable(gtm);
    // Set the global clock frequency to the max
    IfxGtm_Cmu_setGclkFrequency(gtm, frequency);
    // Set the CMU CLK0
    IfxGtm_Cmu_setClkFrequency(gtm, IfxGtm_Cmu_Clk_0, frequency);
    // FXCLK: used by TOM and CLK0: used by ATOM
    IfxGtm_Cmu_enableClocks(gtm, IFXGTM_CMU_CLKEN_FXCLK | IFXGTM_CMU_CLKEN_CLK0);
}

// initialise TOM
IfxGtm_Tom_Pwm_Config tomConfig;    \\configuration structure
IfxGtm_Tom_Pwm_Driver tomHandle;    \\ handle

IfxGtm_Tom_Pwm_initConfig(&tomConfig, gtm);

tomConfig.tomChannel  = IfxGtm_Tom_Ch_0;
tomConfig.period                   = 20;
tomConfig.dutyCycle              = 10;
tomConfig.interrupt.ccu0Enabled = TRUE;
tomConfig.interrupt.isrPriority = TOM0_CH0_PRIO;
tomConfig.pin.outputPin = &IfxGtm_TOM0_0_TOUT106_P10_4_OUT;

IfxGtm_Tom_Pwm_init(&tomHandle, &tomConfig);

TOM will be now generating a PWM signal on the selected port pin while generating selected interrupt according to above configured period and duty cycle.