原创 解释F2812启动的标准C文件

// Step 0.  Include required header files<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

         // DSP28_Device.h: device specific definitions #include statements for

         // all of the peripheral .h definition files.

         // DSP28_Example.h is specific for the given example. 

#include “DSP28_Device.h”

// Prototype statements for functions found within this file.

interrupt void cpu_timer0_isr(void);

void main(void)

{

// Step 1. Initialize System Control registers, PLL, WatchDog, Clocks to default state:

    // This function is found in the DSP28_SysCtrl.c file.

    InitSysCtrl();

// Step 2. Select GPIO for the device or for the specific application:

    // This function is found in the DSP28_Gpio.c file.

    InitGpio();

// Step 3. Initialize PIE vector table:

    // The PIE vector table is initialized with pointers to shell Interrupt

    // Service Routines (ISR).  The shell routines are found in DSP28_DefaultIsr.c.

    // Insert user specific ISR code in the appropriate shell ISR routine in

    // the DSP28_DefaultIsr.c file.

    // Disable and clear all CPU interrupts:

    DINT;

    IER = 0×0000;

    IFR = 0×0000;

    // Initialize Pie Control Registers To <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />DefaultState:

    // This function is found in the DSP28_PieCtrl.c file.

    InitPieCtrl();

    // Initialize the PIE Vector Table To a KnownState:

    // This function is found in DSP28_PieVect.c.

    // This function populates the PIE vector table with pointers

    // to the shell ISR functions found in DSP28_DefaultIsr.c.

    InitPieVectTable();   

// Step 4. Initialize all the Device Peripherals to a known state:

    // This function is found in DSP28_InitPeripherals.c

    InitPeripherals();

// Step 5. User specific functions, Reassign vectors (optional), Enable Interrupts:

    // Initialize CPU Timer 0:

    //        > Set Up For 1 Second Interrupt Period

    //        > Point To “cpu_timer0_isr” function

    // Reassign CPU-Timer0 ISR.

    // Reassign the PIE vector for TINT0 to point to a different ISR then

    // the shell routine found in DSP28_DefaultIsr.c.

    // This is done if the user does not want to use the shell ISR routine

    // but instead wants to use their own ISR.  This step is optional:

    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

    // Include application specific functions. This is for this example:

    // Configure CPU-Timer 0 to interrupt every second:

    ConfigCpuTimer(&CpuTimer0, 100, 1000000);    // 100MHz CPU Freq, 1 second Period (in uSeconds)

     StartCpuTimer0();

    // 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(;;);

}    

// Step 7. Insert all local Interrupt Service Routines (ISRs) and functions here:   

    // If local ISRs are used, reassign vector addresses in vector table as

    // shown in Step 5

interrupt void cpu_timer0_isr(void)

{

    CpuTimer0.InterruptCount++;

    // Acknowledge this interrupt to recieve more interrupts from group 1

    PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;   

}