Trying AD9833 as per Application Note AN-1070

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vineet_barc

Joined Sep 4, 2009
3
Hi,
I am trying to generate sine wave ( using MSP430FG4618 ) from AD9833. Studied the application note AN-1070 but not getting output.

Rich (BB code):
*********************** Code ************************

#include "msp430xG46x.h"

#define FSYNC_AD9833_DIR    P4DIR |= BIT6;
#define FSYNC_AD9833_HIGH   P4OUT |= BIT6;    // Set FSYNC HIGH
#define FSYNC_AD9833_LOW    P4OUT &= ~BIT6;    // Set FSYNC LOW

#define AD9833_REG_CMD      (0 << 14)
#define AD9833_REG_FREQ0    (1 << 14)
#define AD9833_REG_FREQ1    (2 << 14)
#define AD9833_REG_PHASE0   (6 << 13)
#define AD9833_REG_PHASE1   (7 << 13)

/* Command Control Bits */

#define AD9833_B28          (1 << 13)
#define AD9833_HLB          (1 << 12)
#define AD9833_FSEL0        (0 << 11)
#define AD9833_FSEL1        (1 << 11)
#define AD9833_PSEL0        (0 << 10)
#define AD9833_PSEL1        (1 << 10)
#define AD9833_PIN_SW       (1 << 9)
#define AD9833_RESET        (1 << 8)
#define AD9833_SLEEP1       (1 << 7)
#define AD9833_SLEEP12      (1 << 6)
#define AD9833_OPBITEN      (1 << 5)
#define AD9833_SIGN_PIB     (1 << 4)
#define AD9833_DIV2         (1 << 3)
#define AD9833_MODE         (1 << 1)

#define AD9833_OUT_SINUS    ((0 << 5) | (0 << 1) | (0 << 3))
#define AD9833_OUT_TRIANGLE ((0 << 5) | (1 << 1) | (0 << 3))
#define AD9833_OUT_MSB      ((1 << 5) | (0 << 1) | (1 << 3))
#define AD9833_OUT_MSB2     ((1 << 5) | (0 << 1) | (0 << 3))

void AD9833_Write_Word(unsigned int value)
{
    int i;
    char clsb, cmsb;

    clsb = (char)value;
    cmsb = value >> 8;

    FSYNC_AD9833_LOW
    for(i=5;i>0;i--){}            // delay

    while (!(IFG2 & UTXIFG1));  // USART1 TX buffer ready?
    U1TXBUF = cmsb;             //send_AD9833char(cmsb);
    while (!(IFG2 & UTXIFG1));  // USART1 TX buffer ready?
    U1TXBUF = clsb;             //send_AD9833char(clsb);
    while (!(IFG2 & UTXIFG1));  // USART1 TX buffer ready?

    for(i=10;i>0;i--){}            // delay
    FSYNC_AD9833_HIGH

}// AD9833_Write_Word

void main()    // ##################################
{
    int i;

    WDTCTL = WDTPW + WDTHOLD;       // Stop watchdog timer

    FLL_CTL0 |= XCAP14PF;           // Configure load caps
    do // Wait for xtal to stabilize
    {
        IFG1 &= ~OFIFG;                 // Clear OSCFault flag
        for (i = 0x47FF; i > 0; i--);    // Time for flag to set
    }
    while ((IFG1 & OFIFG));            // OSCFault flag still set?

    FSYNC_AD9833_DIR                       
    FSYNC_AD9833_HIGH                   

    P4SEL |= 0x28;                   // P4.3 & P4.5 = SPI SIMO1 & UCLK1
    U1CTL |= SWRST;               // USART logic held in RESET state
    U1CTL |= CHAR|SYNC|MM;   // 8-bit data, SPI mode, Mater mode

    U1TCTL |= CKPL|SSEL1|STC;
    U1BR1 = 0;                  // Baud Rate = (1MHz/8) = 131072
    U1BR0 = 8;                                
    U1MCTL = 0x000;                        

    ME2 |= USPIE1;              // Enables the SPI mode for USART1
    U1CTL &= ~SWRST;            // USART RESET released for operation
   
    AD9833_Write_Word(0x2100);
    AD9833_Write_Word(0x50C7);  // For Generating Sinwave of
    AD9833_Write_Word(0x4000);  // 400Hz...as per Application Note
    AD9833_Write_Word(0xC000);  // AN-1070
    AD9833_Write_Word(0x2000);

     while(1){}


}// main
 
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