New example files

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diff --git a/boards/ek-lm4f120xl/bitband/bitband.c b/boards/ek-lm4f120xl/bitband/bitband.c
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+//*****************************************************************************

+//

+// bitband.c - Bit-band manipulation example.

+//

+// Copyright (c) 2012 Texas Instruments Incorporated.  All rights reserved.

+// Software License Agreement

+// 

+// Texas Instruments (TI) is supplying this software for use solely and

+// exclusively on TI's microcontroller products. The software is owned by

+// TI and/or its suppliers, and is protected under applicable copyright

+// laws. You may not combine this software with "viral" open-source

+// software in order to form a larger program.

+// 

+// THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS.

+// NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT

+// NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

+// A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. TI SHALL NOT, UNDER ANY

+// CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL

+// DAMAGES, FOR ANY REASON WHATSOEVER.

+// 

+// This is part of revision 9453 of the EK-LM4F120XL Firmware Package.

+//

+//*****************************************************************************

+

+#include "inc/hw_memmap.h"

+#include "inc/hw_types.h"

+#include "driverlib/debug.h"

+#include "driverlib/gpio.h"

+#include "driverlib/fpu.h"

+#include "driverlib/pin_map.h"

+#include "driverlib/sysctl.h"

+#include "driverlib/systick.h"

+#include "driverlib/rom.h"

+#include "utils/uartstdio.h"

+

+//*****************************************************************************

+//

+//! \addtogroup example_list

+//! <h1>Bit-Banding (bitband)</h1>

+//!

+//! This example application demonstrates the use of the bit-banding

+//! capabilities of the Cortex-M4F microprocessor.  All of SRAM and all of the

+//! peripherals reside within bit-band regions, meaning that bit-banding

+//! operations can be applied to any of them.  In this example, a variable in

+//! SRAM is set to a particular value one bit at a time using bit-banding

+//! operations (it would be more efficient to do a single non-bit-banded write;

+//! this simply demonstrates the operation of bit-banding).

+//

+//*****************************************************************************

+

+

+//*****************************************************************************

+//

+// The value that is to be modified via bit-banding.

+//

+//*****************************************************************************

+static volatile unsigned long g_ulValue;

+

+//*****************************************************************************

+//

+// The error routine that is called if the driver library encounters an error.

+//

+//*****************************************************************************

+#ifdef DEBUG

+void

+__error__(char *pcFilename, unsigned long ulLine)

+{

+}

+#endif

+

+//*****************************************************************************

+//

+// Delay for the specified number of seconds.  Depending upon the current

+// SysTick value, the delay will be between N-1 and N seconds (i.e. N-1 full

+// seconds are guaranteed, along with the remainder of the current second).

+//

+//*****************************************************************************

+void

+Delay(unsigned long ulSeconds)

+{

+    //

+    // Loop while there are more seconds to wait.

+    //

+    while(ulSeconds--)

+    {

+        //

+        // Wait until the SysTick value is less than 1000.

+        //

+        while(ROM_SysTickValueGet() > 1000)

+        {

+        }

+

+        //

+        // Wait until the SysTick value is greater than 1000.

+        //

+        while(ROM_SysTickValueGet() < 1000)

+        {

+        }

+    }

+}

+

+

+//*****************************************************************************

+//

+// This example demonstrates the use of bit-banding to set individual bits

+// within a word of SRAM.

+//

+//*****************************************************************************

+int

+main(void)

+{

+    unsigned long ulErrors, ulIdx;

+

+    //

+    // Enable lazy stacking for interrupt handlers.  This allows floating-point

+    // instructions to be used within interrupt handlers, but at the expense of

+    // extra stack usage.

+    //

+    ROM_FPULazyStackingEnable();

+

+    //

+    // Set the clocking to run directly from the crystal.

+    //

+    ROM_SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |

+                       SYSCTL_XTAL_16MHZ);

+

+    //

+    // Initialize the UART interface.

+    //

+    ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);

+    GPIOPinConfigure(GPIO_PA0_U0RX);

+    GPIOPinConfigure(GPIO_PA1_U0TX);

+    ROM_GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);

+    UARTStdioInit(0);

+    UARTprintf("\033[2JBit banding...\n");

+

+    //

+    // Set up and enable the SysTick timer.  It will be used as a reference

+    // for delay loops.  The SysTick timer period will be set up for one

+    // second.

+    //

+    ROM_SysTickPeriodSet(ROM_SysCtlClockGet());

+    ROM_SysTickEnable();

+

+    //

+    // Set the value and error count to zero.

+    //

+    g_ulValue = 0;

+    ulErrors = 0;

+

+    //

+    // Print the initial value to the UART.

+    //

+    UARTprintf("\r%08x", g_ulValue);

+

+    //

+    // Delay for 1 second.

+    //

+    Delay(1);

+

+    //

+    // Set the value to 0xdecafbad using bit band accesses to each individual

+    // bit.

+    //

+    for(ulIdx = 0; ulIdx < 32; ulIdx++)

+    {

+        //

+        // Set this bit.

+        //

+        HWREGBITW(&g_ulValue, 31 - ulIdx) = (0xdecafbad >> (31 - ulIdx)) & 1;

+

+        //

+        // Print the current value to the UART.

+        //

+        UARTprintf("\r%08x", g_ulValue);

+

+        //

+        // Delay for 1 second.

+        //

+        Delay(1);

+    }

+

+    //

+    // Make sure that the value is 0xdecafbad.

+    //

+    if(g_ulValue != 0xdecafbad)

+    {

+        ulErrors++;

+    }

+

+    //

+    // Make sure that the individual bits read back correctly.

+    //

+    for(ulIdx = 0; ulIdx < 32; ulIdx++)

+    {

+        if(HWREGBITW(&g_ulValue, ulIdx) != ((0xdecafbad >> ulIdx) & 1))

+        {

+            ulErrors++;

+        }

+    }

+

+    //

+    // Print out the result.

+    //

+    if(ulErrors)

+    {

+        UARTprintf("\nErrors!\n");

+    }

+    else

+    {

+        UARTprintf("\nSuccess!\n");

+    }

+

+    //

+    // Loop forever.

+    //

+    while(1)

+    {

+    }

+}