example_280xadcseq_ovdtest.c

DSP学习板上的例子程序包括 AD转换 CAN总线 SPI SCI

// TI File $Revision: /main/5 $
// Checkin $Date: September 7, 2005   17:36:14 $
// Modified by LSD_Hanbing to suit the LSD_EVM320F2801X, April 21,2007
//###########################################################################
//
// FILE:   Example_280xAdcSeq_ovdTest.c
//
// TITLE:  DSP280x ADC Seq Override mode Test.
//
// ASSUMPTIONS:
//
//    This program requires the DSP280x header files.  
//
//    Make sure the CPU clock speed is properly defined in 
//    DSP280x_Examples.h before compiling this example.
//
//    Connect the signal to be converted to Channel A0.
//
//    As supplied, this project is configured for "boot to SARAM" 
//    operation.  The 280x 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      GPIO18     GPIO29    GPIO34
//       Mode      SPICLKA    SCITXDA
//                 SCITXB
//       -------------------------------------
//       Flash       1          1        1
//       SCI-A       1          1        0
//       SPI-A       1          0        1
//       I2C-A       1          0        0
//       ECAN-A      0          1        1        
//       SARAM       0          1        0  <- "boot to SARAM"
//       OTP         0          0        1
//       I/0         0          0        0 
//          
//
// DESCRIPTION:    
//
//    Channel A0 is converted forever and logged in a buffer (SampleTable)
//    Using sequencer1 in sequencer override mode. Sequencer is Sequential mode
//    with sample rate of 1/(3*133ns) =2.5MHz
//
//    Open a memory window to SampletTable to observe the buffer
//    RUN for a while and stop and see the table contents.
//
//       Watch Variables:
//          SampleTable - Log of converted values.
//          GPIO7       - Toggles on every ADC sequencer flag
//
//###########################################################################
//
// Original source by: S.S.
//
// $TI Release: DSP280x, DSP2801x Header Files V1.41 $
// $Release Date: August 7th, 2006 $
//###########################################################################

#include "DSP280x_Device.h"     // DSP280x Headerfile Include File
#include "DSP280x_Examples.h"   // DSP280x Examples Include File
  
// Determine when the shift to right justify the data takes place
// Only one of these should be defined as 1.  
// The other two should be defined as 0.
#define POST_SHIFT   0  // Shift results after the entire sample table is full
#define INLINE_SHIFT 1  // Shift results as the data is taken from the results regsiter
#define NO_SHIFT     0  // Do not shift the results 
  
// ADC start parameters
#define ADC_MODCLK 0x4   // HSPCLK = SYSCLKOUT/2*ADC_MODCLK2 = 60/(2*4)     = 7.5 MHz
#define ADC_CKPS   0x0   // ADC module clock = HSPCLK/1      = 7.5MHz/(1)   = 7.5 MHz
#define ADC_SHCLK  0x1   // S/H width in ADC module periods                 = 2 ADC cycle
#define AVG        1000  // Average sample limit
#define ZOFFSET    0x00  // Average Zero offset
#define BUF_SIZE   1024  // Sample buffer size

// Global variable for this example
Uint16 SampleTable[BUF_SIZE];


main() 
{
   Uint16 i;
   Uint16 array_index;                     


// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP280x_SysCtrl.c file.
   InitSysCtrl();
      
// Specific clock setting for this example:      
   EALLOW;
   SysCtrlRegs.HISPCP.all = ADC_MODCLK;	// HSPCLK = SYSCLKOUT/ADC_MODCLK
   EDIS;

// Step 2. Initialize GPIO: 
// This example function is found in the DSP280x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio();  // Skipped for this example  
// Enable the pin GPIO7 as output
   EALLOW;
   GpioCtrlRegs.GPAMUX1.all = 0x0;    // GPIO pin
   GpioCtrlRegs.GPADIR.all = 0xFF;     // Output pin
   GpioDataRegs.GPADAT.all =0xFF;     // Close LEDs
   EDIS;

// 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 DSP280x_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 DSP280x_DefaultIsr.c.
// This function is found in DSP280x_PieVect.c.
   InitPieVectTable();

// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP280x_InitPeripherals.c
// InitPeripherals(); // Not required for this example
   InitAdc();         // For this example, init the ADC

// Specific ADC setup for this example:
   AdcRegs.ADCTRL1.bit.ACQ_PS = ADC_SHCLK;  // Sequential mode: Sample rate   = 1/[(2+ACQ_PS)*ADC clock in ns]
					    //                     = 1/(3*133ns) =2.5MHz
					    // If Simultaneous mode enabled: Sample rate = 1/[(3+ACQ_PS)*ADC clock in ns]
   AdcRegs.ADCTRL3.bit.ADCCLKPS = ADC_CKPS;     
   AdcRegs.ADCTRL1.bit.SEQ_CASC = 1;        // 1  Cascaded mode
   AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0x0;
   AdcRegs.ADCTRL1.bit.CONT_RUN = 1;       // Setup continuous run

   AdcRegs.ADCTRL1.bit.SEQ_OVRD = 1;       // Enable Sequencer override feature
   AdcRegs.ADCCHSELSEQ1.all = 0x0;         // Initialize all ADC channel selects to A0
   AdcRegs.ADCCHSELSEQ2.all = 0x0;
   AdcRegs.ADCCHSELSEQ3.all = 0x0;
   AdcRegs.ADCCHSELSEQ4.all = 0x0;
   AdcRegs.ADCMAXCONV.bit.MAX_CONV1 = 0x7;  // convert and store in 8 results registers 


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


// Clear SampleTable
   for (i=0; i<BUF_SIZE; i++)
   {
     SampleTable[i] = 0;
   }

// Start SEQ1
   AdcRegs.ADCTRL2.all = 0x2000;
  
   for(;;)
   {  // Take ADC data and log them in SampleTable array
     
     // Initalize the array index.  This points to the current
     // location within the SampleTable
     array_index = 0;
     
     for (i=0; i<(BUF_SIZE/16); i++)
     {
       // Wait for INT1
       while (AdcRegs.ADCST.bit.INT_SEQ1== 0){}
       GpioDataRegs.GPASET.bit.GPIO7 = 1;  // Set GPIO7 for monitoring  -optional

       AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1;

#if INLINE_SHIFT
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT0)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT1)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT2)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT3)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT4)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT5)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT6)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT7)>>4);
       
#endif //-- INLINE_SHIFT
     
#if NO_SHIFT || POST_SHIFT

       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT0));
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT1));                            
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT2));                            
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT3));                            
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT4));                            
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT5));                            
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT6));                            
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT7));                            
            
#endif //-- NO_SHIFT || POST_SHIFT

       while (AdcRegs.ADCST.bit.INT_SEQ1== 0){}
 	   GpioDataRegs.GPACLEAR.bit.GPIO7 = 1;  // Clear GPIO7 for monitoring  -optional
       AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1;	

#if INLINE_SHIFT

       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT8)>>4);
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT9)>>4);              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT10)>>4);              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT11)>>4);              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT12)>>4);              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT13)>>4);              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT14)>>4);              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT15)>>4);	              
                                      
#endif //-- INLINE_SHIFT              
                                      
#if NO_SHIFT || POST_SHIFT            
                                      
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT8));
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT9));              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT10));              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT11));              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT12));              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT13));              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT14));              
       SampleTable[array_index++]= ( (AdcRegs.ADCRESULT15));              
#endif // -- NO_SHIFT || POST_SHIFT 

	}
	

#if POST_SHIFT
    // For post shifting, shift the ADC results 
    // in the SampleTable buffer after the buffer is full.
    for (i=0; i<BUF_SIZE; i++)
    {
      SampleTable[i] = ((SampleTable[i]) >>4);
    }
#endif // -- POST_SHIFT    
    
    GpioDataRegs.GPACLEAR.bit.GPIO7 = 1;  // Clear GPIO0 for monitoring  -optional
  }
}

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