css_cmake_test/f2833x/examples/timed_led_blink/Example_2833xLEDBlink.c

//###########################################################################
//
// FILE:	Example_2833xLEDBlink.c
//
// TITLE:	Timed LED Blink Example
//
//! \addtogroup f2833x_example_list
//!  <h1>Timer based blinking LED (timed_led_blink)</h1>
//!
//! This example configures CPU Timer0 for a 500 msec period, and toggles the
//! GPIO32 LED on the 2833x once per interrupt. For testing purposes,
//! this example also increments a counter each time the timer asserts an
//! interrupt.
//!
//! Select the appropriate board build configuration to have the correct
//! LED GPIO toggled.
//!
//!  \b Watch \b Variables \n
//!  - CpuTimer0.InterruptCount
//!
//! \b External \b Connections \n
//!  - Monitor the GPIO32 LED blink on (for 500 msec) and off (for 500 msec)
//!
//
//###########################################################################
// $TI Release: $
// $Release Date: $
// $Copyright:
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//
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// modification, are permitted provided that the following conditions 
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// 
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// 
//   Redistributions in binary form must reproduce the above copyright
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//   distribution.
// 
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//   from this software without specific prior written permission.
// 
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################

//
// Included Files
//
#include "DSP28x_Project.h"     // Device Headerfile and Examples Include File

//
// Function Prototypes
//
__interrupt void cpu_timer0_isr(void);

//
// Main
//
void main(void)
{
    //
    // Step 1. Initialize System Control:
    // PLL, WatchDog, enable Peripheral Clocks
    // This example function is found in the DSP2833x_SysCtrl.c file.
    //
    InitSysCtrl();

    //
    // Step 2. Initialize GPIO:
    // This example function is found in the DSP2833x_Gpio.c file and
    // illustrates how to set the GPIO to it's default state.
    //
    //InitGpio();  // Skipped for this example

    //
    // Step 3. Clear all interrupts and initialize PIE vector table:
    // Disable CPU interrupts
    //
    DINT;

    //
    // Initialize the PIE control registers to their default state.
    // The default state is all PIE interrupts disabled and flags
    // are cleared.
    // This function is found in the DSP2833x_PieCtrl.c file.
    //
    InitPieCtrl();

    //
    // Disable CPU interrupts and clear all CPU interrupt flags:
    //
    IER = 0x0000;
    IFR = 0x0000;

    //
    // Initialize the PIE vector table with pointers to the shell Interrupt
    // Service Routines (ISR).
    // This will populate the entire table, even if the interrupt
    // is not used in this example.  This is useful for debug purposes.
    // The shell ISR routines are found in DSP2833x_DefaultIsr.c.
    // This function is found in DSP2833x_PieVect.c.
    //
    InitPieVectTable();

    //
    // Interrupts that are used in this example are re-mapped to
    // ISR functions found within this file.
    //
    EALLOW;         // This is needed to write to EALLOW protected registers
    PieVectTable.TINT0 = &cpu_timer0_isr;
    EDIS;    // This is needed to disable write to EALLOW protected registers

    //
    // Step 4. Initialize the Device Peripheral. This function can be
    //         found in DSP2833x_CpuTimers.c
    //
    InitCpuTimers();   // For this example, only initialize the Cpu Timers
#if (CPU_FRQ_150MHZ)
    //
    // Configure CPU-Timer 0 to interrupt every 500 milliseconds:
    // 150MHz CPU Freq, 50 millisecond Period (in uSeconds)
    //
    ConfigCpuTimer(&CpuTimer0, 150, 500000);
#endif
#if (CPU_FRQ_100MHZ)
    //
    // Configure CPU-Timer 0 to interrupt every 500 milliseconds:
    // 100MHz CPU Freq, 50 millisecond Period (in uSeconds)
    //
    ConfigCpuTimer(&CpuTimer0, 100, 500000);
#endif

    //
    // To ensure precise timing, use write-only instructions to write to the
    // entire register. Therefore, if any of the configuration bits are changed
    // in ConfigCpuTimer and InitCpuTimers (in DSP2833x_CpuTimers.h), the
    // below settings must also be updated.
    //

    //
    // Use write-only instruction to set TSS bit = 0
    //
    CpuTimer0Regs.TCR.all = 0x4000;

    //
    // Step 5. User specific code, enable interrupts
    //
#if (_EZDSP_BOARD)
    //
    // Configure GPIO32 as a GPIO output pin
    //
    EALLOW;
    GpioCtrlRegs.GPBMUX1.bit.GPIO32 = 0;
    GpioCtrlRegs.GPBDIR.bit.GPIO32 = 1;
    EDIS;
#else
    //
    // Configure GPIO31 as a GPIO output pin
    //
    EALLOW;
    GpioCtrlRegs.GPAMUX2.bit.GPIO31 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO31 = 1;
    EDIS;
#endif

    //
    // Enable CPU INT1 which is connected to CPU-Timer 0:
    //
    IER |= M_INT1;

    //
    // Enable TINT0 in the PIE: Group 1 interrupt 7
    //
    PieCtrlRegs.PIEIER1.bit.INTx7 = 1;

    //
    // Enable global Interrupts and higher priority real-time debug events
    //
    EINT;           // Enable Global interrupt INTM
    ERTM;           // Enable Global realtime interrupt DBGM

    //
    // Step 6. IDLE loop. Just sit and loop forever (optional):
    //
    for(;;);
}

//
// cpu_timer0_isr -
//
__interrupt void
cpu_timer0_isr(void)
{
    CpuTimer0.InterruptCount++;

#if (_EZDSP_BOARD)
    //
    // Toggle GPIO32 once per 500 milliseconds
    //
    GpioDataRegs.GPBTOGGLE.bit.GPIO32 = 1;
#else
    //
    // Toggle GPIO31 once per 500 milliseconds
    //
    GpioDataRegs.GPATOGGLE.bit.GPIO31 = 1;
#endif

    //
    // Acknowledge this interrupt to receive more interrupts from group 1
    //
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;
}

//
// End of File
//