using part TM4C1294KCPDT, having problems initialising Timer / PWM

Hi forum,

I'm designed an controlelr with the TM4C1294KCPDT. Now I try to initialize  the Timer 5_A to generate a PWM-signal.

I started with the example code comming with CCS6 Tiva.

Access to Pin 71 (PM7) as GPIO works well, but I can't get a waveform from the Timer.

Someone have a idea what is wrong ? Thanks for your comment.

Here my short program: (labels PART_TM4C1294KCPDT and TARGET_IS_TM4C129_RA1 are defined in my CCS6-project)

#include <stdbool.h>
#include <stdint.h>

#include "inc/tm4c1294kcpdt.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"

#include "driverlib/sysctl.h"
#include "driverlib/pin_map.h"
#include "driverlib/gpio.h"
#include "driverlib/timer.h"


//*****************************************************************************
//
//! This function initializes PWM output at pin PM7
//!
//! \param none
//!
//! \return nothing
//
//*****************************************************************************
void main( void)
{
    //
    // Set the system clock to run at 16MHz from the PLL.
    //
    SysCtlClockFreqSet( (SYSCTL_OSC_MAIN | SYSCTL_USE_PLL | SYSCTL_CFG_VCO_320), 16000000);

    //
    // The Timer used for CLK_OUT peripheral must be enabled for use.
    //
    SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER5);
    SysCtlDelay(2);
    
    //
    // Enable this peripheral.
    //
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOM);
    SysCtlDelay(2);
    
    //
    // 16/32-Bit Timer 5 Capture/Compare/PWM 1.
    // Configure the GPIO pin muxing for the Timer/CCP function.
    //
    GPIOPinConfigure(GPIO_PM7_T5CCP1);
    
    //
    // Configures pin(s) for use as CLK_OUT
    //
    GPIOPinTypeTimer(GPIO_PORTM_BASE, GPIO_PIN_7);

    //
    // Disable and Configure CLK_OUT-Timer as a 16-bit PWM timer.
    //
    TimerConfigure(TIMER5_BASE, TIMER_CFG_SPLIT_PAIR | TIMER_CFG_A_PWM);

    //
    // From the load value (cycle time) down to match value the signal will be high.
    // From the match value to 0 the timer will be low.
    // clkout-frequency is 1 / (80MHz / (high + low))
    //
    TimerLoadSet(TIMER5_BASE, TIMER_A, 50000 );
    TimerMatchSet(TIMER5_BASE, TIMER_A, 25000);

    //
    // Enable CLK_OUT-Timer.
    //
    TimerEnable(TIMER5_BASE, TIMER_A);

    //
    // loop forever
    //
    while(1) ;

}