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只看该作者 · 2013-10-19 21:21

// TI File $Revision: /main/1 $
// Checkin $Date: September 21, 2007 08:58:44 $
//###########################################################################
//
// FILE: Example_2833xLedBlink.c
//
// TITLE: DSP2833x eZdsp LED Blink Getting Started Program.
//
// ASSUMPTIONS:
//
// This program requires the DSP2833x header files.
//
//
// As supplied, this project is configured for "boot to SARAM"
// operation.  The 2833x Boot Mode table is shown below.
// For information on configuring the boot mode of an eZdsp,
// please refer to the documentation included with the eZdsp,
//
//    $Boot_Table:
//
//       GPIO87 GPIO86    GPIO85 GPIO84
//       XA15    XA14    XA13    XA12
//          PU    PU       PU    PU
//       ==========================================
//          1       1       1       1 Jump to Flash
//          1       1       1       0 SCI-A boot
//          1       1       0       1 SPI-A boot
//          1       1       0       0 I2C-A boot
//          1       0       1       1 eCAN-A boot
//          1       0       1       0 McBSP-A boot
//          1       0       0       1 Jump to XINTF x16
//          1       0       0       0 Jump to XINTF x32
//          0       1       1       1 Jump to OTP
//          0       1       1       0 Parallel GPIO I/O boot
//          0       1       0       1 Parallel XINTF boot
//          0       1       0       0 Jump to SARAM       <- "boot to SARAM"
//          0       0       1       1 Branch to check boot mode
//          0       0       1       0 Boot to flash, bypass ADC cal
//          0       0       0       1 Boot to SARAM, bypass ADC cal
//          0       0       0       0 Boot to SCI-A, bypass ADC cal
//                                           Boot_Table_End$
//
// DESCRIPTION:
//
// This example configures CPU Timer0 for a 500 msec period, and toggles the GPIO32
// LED on the 2833x eZdsp once per interrupt. For testing purposes, this example
// also increments a counter each time the timer asserts an interrupt.
//
//    Watch Variables:
//       CpuTimer0.InterruptCount
//
//    Monitor the GPIO32 LED blink on (for 500 msec) and off (for 500 msec) on the 2833x eZdsp.
//
//###########################################################################
// $TI Release: DSP2833x Header Files V1.10 $
// $Release Date: February 15, 2008 $
//###########################################################################

#include "DSP2833x_Device.h"    // DSP2833x Headerfile Include File
#include "DSP2833x_Examples.h" // DSP2833x Examples Include File

// Prototype statements for functions found within this file.
interrupt void cpu_timer0_isr(void);
unsigned int Count,Flag;

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();//要对系统时钟初始化，DSP28335禁止看门狗，然后再经过PLL决定系统时钟以及高低速时钟和对需要的外设是否提供外设;

// Step 2. Initalize 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;//关中断DINT 关闭全局中断，跟51中EA=0;效果相似

// 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();//初始化PIE模块，初始化中断寄存器

// 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();//对向量表进行初始化;初始化PIE矢量表

//烧写flash
// MemCopy(&RamfuncsLoadStart, &RamfuncsLoadEnd, &RamfuncsRunStart);  //烧写flash
// InitFlash(); //flash初始化

// 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;

Count = 0; //初始化变量
Flag=0;

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 //初始化CPU定时器，
#if (CPU_FRQ_150MHZ)// DSP28_28335||DSP28_28334
// Configure CPU-Timer 0 to interrupt every 500 milliseconds:
// 150MHz CPU Freq, 50 millisecond Period (in uSeconds)
ConfigCpuTimer(&CpuTimer0, 150, 1000000);// 150 MHz CPU Freq (30 MHz input freq) by DEFAULT
#endif
#if (CPU_FRQ_100MHZ)// DSP28_28332 device only
// Configure CPU-Timer 0 to interrupt every 500 milliseconds:
// 100MHz CPU Freq, 50 millisecond Period (in uSeconds)
ConfigCpuTimer(&CpuTimer0, 100, 500000);// 100 Mhz CPU Freq (20 MHz input freq)
#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.

CpuTimer0Regs.TCR.all = 0x4001; // Use write-only instruction to set TSS bit = 0 开启定时器

// Step 5. User specific code, enable interrupts:

// Configure GPIO0-3 as a GPIO output pin
EALLOW;//EALLOW一般和EDIS配套使用，EALLOW就是将该标志位置位，允许对受保护的寄存器操作，
   //在对受保护的寄存器操作之后，用EDIS恢复寄存器的被保护状态。

GpioCtrlRegs.GPAMUX1.bit.GPIO0 = 0;//配置GPIO00为普通数字I/O 0  外设 1
GpioCtrlRegs.GPADIR.bit.GPIO0 = 1;//配置GPIO00为输出1 输入0
GpioCtrlRegs.GPAMUX1.bit.GPIO1 = 0;
GpioCtrlRegs.GPADIR.bit.GPIO1 = 1;
GpioCtrlRegs.GPAMUX1.bit.GPIO2 = 0;
GpioCtrlRegs.GPADIR.bit.GPIO2 = 1;
GpioCtrlRegs.GPAMUX1.bit.GPIO3 = 0;
GpioCtrlRegs.GPADIR.bit.GPIO3 = 1;
GpioCtrlRegs.GPAMUX1.bit.GPIO4 = 0;
GpioCtrlRegs.GPADIR.bit.GPIO4 = 1;
GpioCtrlRegs.GPAMUX1.bit.GPIO5 = 0;
GpioCtrlRegs.GPADIR.bit.GPIO5 = 1;
GpioCtrlRegs.GPAMUX2.bit.GPIO23 = 0;
GpioCtrlRegs.GPADIR.bit.GPIO23 = 1;
GpioCtrlRegs.GPBMUX1.bit.GPIO36 = 0;
GpioCtrlRegs.GPBDIR.bit.GPIO36 = 1;
EDIS;
/****************设置中断*******************/
/****************设置中断向量组和中断号*******************/
// Enable CPU INT1 which is connected to CPU-Timer 0:
IER |= M_INT1;//中断使能寄存器中断向量组INT1=0x01 timer0

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

// Enable global Interrupts and higher priority real-time debug events:
EINT; // Enable Global interrupt INTM  打开全局中断，跟51中EA=1;效果相似
ERTM; // Enable Global realtime interrupt DBGM  使能调试事件

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

/****************中断函数中用户代码*******************/
interrupt void cpu_timer0_isr(void)
{
CpuTimer0.InterruptCount++;
GpioDataRegs.GPATOGGLE.bit.GPIO0 = 1; // Toggle GPIO0 once per 500 milliseconds
GpioDataRegs.GPATOGGLE.bit.GPIO1 = 1; // Toggle GPIO1 once per 500 milliseconds
GpioDataRegs.GPATOGGLE.bit.GPIO2 = 1; // Toggle GPIO2 once per 500 milliseconds
GpioDataRegs.GPATOGGLE.bit.GPIO3 = 1; // Toggle GPIO3 once per 500 milliseconds
GpioDataRegs.GPATOGGLE.bit.GPIO4 = 1; // Toggle GPIO3 once per 500 milliseconds
GpioDataRegs.GPATOGGLE.bit.GPIO5 = 1; // Toggle GPIO3 once per 500 milliseconds
GpioDataRegs.GPATOGGLE.bit.GPIO23 = 1; // Toggle GPIO3 once per 500 milliseconds
GpioDataRegs.GPBTOGGLE.bit.GPIO36 = 1; // Toggle GPIO3 once per 500 milliseconds
// Acknowledge this interrupt to receive more interrupts from group 1
PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;//清除相应的中断位，以便响应下次中断
}

//===========================================================================
// No more.
//===========================================================================