adc.c

DSP 2812 开发的一些功能介绍, 内容丰富

/**********************************************************************
* File: Adc.c
* Devices: TMS320F2808, TMS320F2806, TMS320F2801
* Author: David M. Alter, Texas Instruments Inc.
* History:
*   02/11/05 - original (D. Alter)
**********************************************************************/

#include "DSP280x_Device.h"

// EXAMPLE_BIOS or EXAMPLE_NONBIOS are defined in the CCS project build options
#ifdef EXAMPLE_BIOS
    #include "example_BIOS.h"
#endif

#ifdef EXAMPLE_NONBIOS
    #include "example_nonBIOS.h"
#endif


/**********************************************************************
* Function: InitAdc()
*
* Description: Initializes the ADC on the F280x.
**********************************************************************/
void InitAdc(void)
{

/*** Reset the ADC module ***/
	AdcRegs.ADCTRL1.bit.RESET = 1;		// Reset the ADC module

// Must wait 2 ADCCLK periods for the reset to take effect.  The ADC is 
// already reset after a DSP reset, but this example is just showing good
// coding practice to reset the peripheral before configuring it (as you
// never know why the DSP has started the code over again from the
// beginning).  Assuming a 12.5 MHz ADCCLK was previously configured, and
// a 100 MHz SYSCLKOUT, the wait period of 2 ADCCLK periods equates to 16
// CPU clocks.  This is the example being used below.
 
	asm(" RPT #14 || NOP");				// Must for ADC reset to take effect

/*** Select the ADC reference ***/
	AdcRegs.ADCREFSEL.bit.REF_SEL = 0;	// 0:internal, 1:external
	
/*** Power-up the ADC ***/
	AdcRegs.ADCTRL3.all = 0x00E8;		// Power-up reference and main ADC
/*
 bit 15-8      0's:    reserved
 bit 7-6       11:     ADCBGRFDN, reference power, 00=off, 11=on
 bit 5         1:      ADCPWDN, main ADC power, 0=off, 1=on
 bit 4-1       0100:   ADCCLKPS, clock prescaler, FCLK=HSPCLK/(2*ADCCLKPS)
 bit 0         0:      SMODE_SEL, 0=sequential sampling, 1=simultaneous sampling
*/

	DelayUs(5000);						// Wait 5ms before using the ADC

/*** Configure the other ADC register ***/
	AdcRegs.ADCMAXCONV.all = 0x0000;
/*
 bit 15-7      0's:    reserved
 bit 6-4       000:    MAX_CONV2 value
 bit 3-0       0000:   MAX_CONV1 value (0 means 1 conversion)
*/

	AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0;	// Convert Channel 0

	AdcRegs.ADCTRL1.all = 0x0710;
/*
 bit 15        0:      reserved
 bit 14        0:      RESET, 0=no action, 1=reset ADC
 bit 13-12     00:     SUSMOD, 00=ignore emulation suspend
 bit 11-8      0111:   ACQ_PS (Acquisition), 0111 = 8 x ADCCLK
 bit 7         0:      CPS (Core clock), 0: ADCCLK=FCLK/1, 1: ADCCLK=FCLK/2
 bit 6         0:      CONT_RUN, 0=start/stop mode, 1=continuous run
 bit 5         0:      SEQ_OVRD, 0=disabled, 1=enabled
 bit 4         1:      SEQ_CASC, 0=dual sequencer, 1=cascaded sequencer
 bit 3-0       0000:   reserved
*/

	AdcRegs.ADCTRL2.all = 0x0900;
/*
 bit 15        0:      ePWM_SOCB_SEQ, 0=no action
 bit 14        0:      RST_SEQ1, 0=no action
 bit 13        0:      SOC_SEQ1, 0=clear any pending SOCs
 bit 12        0:      reserved
 bit 11        1:      INT_ENA_SEQ1, 1=enable interrupt
 bit 10        0:      INT_MOD_SEQ1, 0=int on every SEQ1 conv
 bit 9         0:      reserved
 bit 8         1:      ePWM_SOCA_SEQ1, 1=SEQ1 start from ePWM_SOCA trigger
 bit 7         0:      EXT_SOC_SEQ1, 1=SEQ1 start from ADCSOC pin
 bit 6         0:      RST_SEQ2, 0=no action
 bit 5         0:      SOC_SEQ2, no effect in cascaded mode
 bit 4         0:      reserved
 bit 3         0:      INT_ENA_SEQ2, 0=int disabled
 bit 2         0:      INT_MOD_SEQ2, 0=int on every other SEQ2 conv
 bit 1         0:      reserved
 bit 0         0:      ePWM_SOCB_SEQ2, 0 = no action
*/

/*** Enable the ADC interrupt ***/
	PieCtrlRegs.PIEIER1.bit.INTx6 = 1;	// Enable ADCINT in PIE group 1
	IER |= 0x0001;						// Enable INT1 in IER to enable PIE group

} // end AdcInit()


/*** end of file *****************************************************/