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// TI File $Revision: /main/2 $ 
// Checkin $Date: April 28, 2005   15:17:26 $ 
//########################################################################### 
// 
// FILE:   Example_281xAdcSeqModeTest.c 
// 
// TITLE:  DSP281x ADC Seq Mode Test. 
// 
// ASSUMPTIONS: 
// 
//          This program requires the DSP281x V1.00 header files.   
//          As supplied, this project is configured for "boot to H0" operation.   
//  
//          Make sure the CPU clock speed is properly defined in  
//          DSP281x_Examples.h before compiling this example. 
// 
//          Connect the signal to be converted to channel A0. 
// 
// DESCRIPTION:     
// 
//          Channel A0 is converted forever and logged in a buffer (SampleTable) 
// 
//          Open a memory window to SampleTable to observe the buffer 
//          RUN for a while and stop and see the table contents. 
// 
//          Watch Variables: 
//             SampleTable - Log of converted values. 
// 
//########################################################################### 
// $TI Release: $ 
// $Release Date: $ 
//########################################################################### 
 
#include "DSP281x_Device.h"     // DSP281x Headerfile Include File 
#include "DSP281x_Examples.h"   // DSP281x Examples Include File 
 
// ADC start parameters 
#define ADC_MODCLK 0x3   // HSPCLK = SYSCLKOUT/2*ADC_MODCLK2 = 150/(2*3)         = 25MHz 
#define ADC_CKPS   0x1   // ADC module clock = HSPCLK/2*ADC_CKPS   = 25MHz/(1*2) = 12.5MHz 
#define ADC_SHCLK  0xf   // S/H width in ADC module periods                      = 16 ADC clocks 
#define AVG        1000  // Average sample limit 
#define ZOFFSET    0x00  // Average Zero offset 
#define BUF_SIZE   2048  // Sample buffer size 
 
// Global variable for this example 
Uint16 SampleTable[BUF_SIZE]; 
 
main()  
{ 
   Uint16 i; 
 
// Step 1. Initialize System Control: 
// PLL, WatchDog, enable Peripheral Clocks 
// This example function is found in the DSP281x_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 DSP281x_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 DSP281x_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 DSP281x_DefaultIsr.c. 
// This function is found in DSP281x_PieVect.c. 
   InitPieVectTable(); 
 
// Step 4. Initialize all the Device Peripherals: 
// This function is found in DSP281x_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; 
   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 
 
 
// Step 5. User specific code, enable interrupts: 
 
 
// Clear SampleTable 
   for (i=0; i>4) );  
     } 
   } 
} 
 
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// No more. 
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