CCS/SW-EK-TM4C123GXL: TM4C123GH6PM USB DFU Boot Loader

Tool/software: Code Composer Studio

I have read all of the available material to try and get the TM4C123GH6PM processor on my REV A  EK-TM4C123GXL development board into USB DFU mode. I am using the code below and I am able to compile and load the sw using CCS. However, when I plug the eval board in using the device port (and switch the PWR SELECT to "DEVICE") and bring up LM Flash Programmer (Build1613) there is no USB DFU device identified. I have confirmed that I can force the board into USB DFU mode using LM Flash to erase the flash. I have tried two different eval boards. I have tried loading the software as a .bin... No dice.

A little more info:

Device does not show up in Device Manager as "Stellaris Device Firmware Upgrade" unless flash is erased by LM Flash Programmer. 

I have followed the example code provided for the TM4C129x along with reading and trying what seems to be every possible solution in a half dozen other forum entries.

I have the part as:TARGET_IS_TM4C123_RA3 under Properties > Build > ARM Compiler > Predefined Symbols; in the Pre-defined NAME field. Also in this field I have PART_TM4C123GH6PM

I am running CCS Version: 7.0.0.00043 & TivaWare_C_Series-2.1.4.178

Thanks in advance for any help.

CODE:

#include <stdint.h> // Variable definitions for the C99 standard.
#include <stdbool.h> // Boolean definitions for the C99 standard.

#include "inc/tm4c123gh6pm.h" // Definitions for the interrupt and register assignments.
#include "inc/hw_memmap.h" // Memory map definitions of the Tiva C Series device.
#include "inc/hw_types.h" // Definitions of common types and macros.

#include "driverlib/rom.h"
#include "driverlib/rom_map.h"
#include "inc/hw_nvic.h"
#include "driverlib/usb.h"
#include "usblib/usblib.h"
#include "usblib/device/usbdevice.h"
#include "usblib/device/usbddfu-rt.h"

#include "driverlib/sysctl.h" // Definitions and macros for System Control API of DriverLib.
#include "driverlib/interrupt.h" // Defines and macros for NVIC Controller API of DriverLib.
#include "driverlib/gpio.h" // Definitions and macros for GPIO API of DriverLib.
#include "driverlib/timer.h" // Defines and macros for Timer API of DriverLib.
#include "driverlib/pin_map.h" //Mapping of peripherals to pins for all parts.
#include "driverlib/uart.h" // Definitions and macros for UART API of DriverLib.
#include "driverlib/adc.h" // Definitions for ADC API of DriverLib.

//#define TARGET_IS_TM4C123_RA3

uint32_t sys_clock;

int main(void)
{


    // Configure system clock at 40 MHz.
    ROM_SysCtlClockSet(SYSCTL_SYSDIV_5|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN);
    sys_clock = ROM_SysCtlClockGet();



    USBDCDTerm(0);

    ROM_IntMasterDisable();

    ROM_SysTickIntDisable();
    ROM_SysTickDisable();

    HWREG(NVIC_DIS0) = 0xffffffff;
    HWREG(NVIC_DIS1) = 0xffffffff;
    HWREG(NVIC_DIS2) = 0xffffffff;
    HWREG(NVIC_DIS3) = 0xffffffff;
    HWREG(NVIC_DIS4) = 0xffffffff;


    ROM_SysCtlPeripheralEnable(GPIO_PORTD_BASE);
    ROM_GPIOPinTypeUSBAnalog(GPIO_PORTD_BASE, GPIO_PIN_4);
    ROM_GPIOPinTypeUSBAnalog(GPIO_PORTD_BASE, GPIO_PIN_5);


    ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_USB0);
    ROM_SysCtlPeripheralReset(SYSCTL_PERIPH_USB0);

  //  ROM_GPIOPinTypeUSBAnalog(GPIO_PORTD_BASE, GPIO_PIN_4);
  // ROM_GPIOPinTypeUSBAnalog(GPIO_PORTD_BASE, GPIO_PIN_5);


    ROM_SysCtlUSBPLLEnable();

    ROM_SysCtlDelay(sys_clock/3);

    ROM_IntMasterEnable();

    ROM_UpdateUSB(0);


    while(1) {
             }
    }