Dual DDS control with launchpad & 430G2553 problem

[wa3tfs 0]

I've written code to control a DDS for a transmitter project.  It works perfectly and generates the required local oscillator output.  I then wanted to add control for a second DDS module to generate two different frequencies for the BFO frequency.  Seems it should be simple, just duplicate the control for DDS1 for DDS2 however, it seems I can't get the second DDS to program.  I know the hardware is good as I can substitute one DDS for another with the same result.  I don't know if I'm chasing a launchpad problem or a software problem.  I'll attach my code and if anyone can suggest a solution, I would greatly appreciate it.  Also, if anyone can use this code, please feel free to do so.

 

code follows:

#include <msp430g2553.h>
/* transmit controller program
 * modified Dec 2016 to add functions to control second dds for BFO
 * modified april 2 2015 by WA3TFS to convert arduino to launchpad
 * DDS frequency set up and control program using launchpad and 430G2553
 * If using ver 1.4 or below board, jumper RXD and TXD diagonally
 * Original AD9851 DDS sketch by Andrew Smallbone at www.rocketnumbernine.com
 * Modified for programming the inexpensive AD9850 ebay DDS modules
 * WA3TFS Added serial function to load frequency and control of 5 low pass filters
  
 */
#define W_CLK 7        // Pin 7 - connect to AD9850 module word load clock pin (CLK)
#define FQ_UD 10       // Pin 10 - connect to freq update pin (FQ)
#define DATA 9         // Pin 9 - connect to serial data load pin (DATA)
#define RESET 8        // Pin 8 - connect to reset pin (RST).
#define pulseHigh(pin) {digitalWrite(pin, HIGH); digitalWrite(pin, LOW); }
#define ONESXTY 6      // select 160 meter band filter
#define EIGHTY 5       // select 80 meter band filter
#define FORTY 11       //select 40 meter band filter
#define TWENTY 15      //select 20 meter and above filter
#define THIRTY 18      //SELECT 15 meter and above filter
#define B_CLK 12       //clock BFO DDS
#define BQ_UD 13       //load BFO DDS
#define BATA 14        //BFO frequency
#define BESET 2        //BFO reset

long bfo;
long frequency;
long val;
long val2;
long val3;
long val4;
long bfreq;

// transfers a byte, a bit at a time, LSB first to the 9850 via serial DATA line
void tfr_bfobyte(byte data) 
{
  for (int f=0; f<8; f++, data>>=1) {
    digitalWrite(BATA, data & 0x01);
    pulseHigh(B_CLK);   //after each bit sent, CLK is pulsed high
  }
}

// transfers a byte, a bit at a time, LSB first to the 9850 via serial DATA line
void tfr_byte(byte data) 
{
  for (int i=0; i<8; i++, data>>=1) {
    digitalWrite(DATA, data & 0x01);
    pulseHigh(W_CLK);   //after each bit sent, CLK is pulsed high
  }
}

// frequency calc from datasheet page 8 = <sys clock> * <frequency tuning word>/2^32

void sendFrequency(double frequency) {
      //Serial.print(frequency);  //print actual value to monitor to debug **************added
  int32_t freq = frequency * 34.35973836;  // note 125 MHz clock on 9850
  for (int b=0; b<4; b++, freq>>=8) {
    tfr_byte(freq & 0xFF);
  }
  tfr_byte(0x000);   // Final control byte, all 0 for 9850 chip
  pulseHigh(FQ_UD);  // Done!  Should see output
  
}

// frequency calc from datasheet page 8 = <sys clock> * <BFO DDS frequency tuning word>/2^32
void sendBfo(double bfo) {
        //Serial.print(bfreq);  //print actual value to monitor to debug **************added

  int32_t bfreq = bfo * 34.35973836;  // note 125 MHz clock on 9850
  for (int e=0; e<4; e++, bfreq>>=8) {
    tfr_bfobyte(bfreq & 0xFF);
  }
  tfr_byte(0x000);   // Final control byte, all 0 for 9850 chip
  pulseHigh(BQ_UD);  // Done!  Should see BFO output
  }

//added this code to talk serially
void setup() {
  Serial.begin(9600);
  // configure launchpad data pins for output
  pinMode(FQ_UD, OUTPUT);
  pinMode(W_CLK, OUTPUT);
  pinMode(DATA, OUTPUT);
  pinMode(RESET, OUTPUT);
  pinMode(ONESXTY, OUTPUT);
  pinMode(EIGHTY, OUTPUT);
  pinMode(FORTY, OUTPUT);
  pinMode(TWENTY, OUTPUT);
  pinMode(THIRTY, OUTPUT);
  pinMode(B_CLK, OUTPUT);
  pinMode(BQ_UD, OUTPUT);
  pinMode(BATA, OUTPUT);
  pinMode(BESET, OUTPUT);
  digitalWrite(ONESXTY, LOW);  //SET UP INITIAL STATE OF CONTROL PINS
  digitalWrite(EIGHTY, LOW);
  digitalWrite(FORTY, LOW);
  digitalWrite(TWENTY, LOW);
  digitalWrite(THIRTY,HIGH);   //ON START UP ACTIVATE THIS FILTER
  pulseHigh(RESET);  //main dds reset
  pulseHigh(W_CLK);  //main dds clock
  pulseHigh(FQ_UD);  // this pulse enables updates main dds 
  pulseHigh(BESET);  //bfo dds reset
  pulseHigh(B_CLK);  //bfo dds clock
  pulseHigh(BQ_UD);  // this pulse updates bfo dds
  bfo = 899720;     //initial set of bfo freq on startup
}

//added this below to input required frequencies and offsets
//this also selects the proper low pass filter for the frequencies programmed
void loop()
{
  
  if (Serial.available()) {
    frequency = Serial.parseInt();

    Serial.println(frequency);
    if (frequency<1000) goto loop1;
      
    if (frequency>1500000)
    {
          digitalWrite(ONESXTY, HIGH);   //IF TRUE TURN OF THIS FILTER 
     if (frequency<(2100000)) 
          digitalWrite(ONESXTY, HIGH);   //IF TRUE TURN ON THIS FILTER
            else 
              digitalWrite(ONESXTY, LOW);  //TURN OFF OTHER LOW PASS FILTERS
              digitalWrite(EIGHTY, LOW);
              digitalWrite(FORTY, LOW);7100000
              7100000
              
              digitalWrite(TWENTY, LOW);
              digitalWrite(THIRTY, LOW);
                 bfo = (8997200);

    }
      if (frequency>2100001)
    {
          digitalWrite(EIGHTY, HIGH);   //IF TRUE TURN ON THIS FILTER 
     if (frequency<(4000000)) 
          digitalWrite(EIGHTY, HIGH);   //IF TRUE TURN ON THIS FILTER
            else 
              digitalWrite(EIGHTY, LOW);   //TURN OFF OTHER LOW PASS FILTERS
              digitalWrite(ONESXTY, LOW);
              digitalWrite(FORTY, LOW);
              digitalWrite(TWENTY, LOW);
              digitalWrite(THIRTY, LOW);
                 bfo = (899720);

    }
      if (frequency>4000001)
    {
          digitalWrite(FORTY, HIGH);   //IF TRUE TURN ON THIS FILTER 
     if (frequency<(7400000)) 
          digitalWrite(FORTY, HIGH);   //IF TRUE TURN ON THIS FILTE
            else
              digitalWrite(FORTY, LOW); //TURN OFF OTHER LOW PASS FILTERS
              digitalWrite(ONESXTY, LOW);
              digitalWrite(EIGHTY, LOW);
              digitalWrite(TWENTY, LOW);
              digitalWrite(THIRTY, LOW);
                 bfo = (899720);

    }
     if (frequency>7400001)
    {
          digitalWrite(TWENTY, HIGH);   //IF TRUE TURN ON THIS FILTER 
     if (frequency<(14400000)) 
          digitalWrite(TWENTY, HIGH);   //IF TRUE TURN ON THIS FILTE
            else 
              digitalWrite(TWENTY, LOW);   //TURN OFF OTHER LOW PASS FILTERS
              digitalWrite(ONESXTY, LOW);
              digitalWrite(EIGHTY, LOW);
              digitalWrite(FORTY, LOW);
              digitalWrite(THIRTY, LOW);
                 bfo = (900000);

    }
     if (frequency>14400001)
    {
          digitalWrite(THIRTY, HIGH);   //IF TRUE TURN ON THIS FILTER 
     if (frequency<(35000000)) 
          digitalWrite(THIRTY, HIGH);   //IF TRUE TURN ON THIS FILTER
            else 
              digitalWrite(THIRTY, LOW);  //TURN OFF OTHER LOW PASS FILTERS
              digitalWrite(ONESXTY, LOW);
              digitalWrite(EIGHTY, LOW);
              digitalWrite(FORTY, LOW);
              digitalWrite(TWENTY, LOW);
                 bfo = (900000);
    }
    
    
      frequency = (frequency + 8999825);// create local oscillator injection offset +/- from 9Mhz to correct osc. (freq 8999825)
      bfo = bfo;
    sendFrequency(frequency);  // send LO frequency to DDS ctrl.Offset 500 corrects frequency
      Serial.print(frequency);  //print actual value to monitor to debug offset not displayed
      Serial.print(bfo);  //print actual value to monitor to debug
    sendBfo(bfo);  // send BFO frequency to DDS ctrl.
      
      
loop1:;

  }
}

[mgh 11]

You have separate routines:

  void tfr_bfobyte(byte data) 
  void tfr_byte(byte data) 

And sendFrequency() calls tfr_byte(), but sendBfo() also calls tfr_byte() at one place.

 

I don't know if that's a problem or not.  My apologies for the noise if I'm off-base.

 

(Sometimes I have to print the code out on paper and spread it out in front of me, to see what's actually going on.)

[wa3tfs 0]

Mike, 

You did point me in the right direction.  That statement was where the problem was.  I corrected it and now the second dds programs properly.  It's funny how you can look at the same code dozens of times and not see it!  I still have to fix a problem with a variable setting that passes the frequency for the second dds but I can fix that.

Thanks for your help.

Jim