AD9850 useful test sketch for Arduino(-s)

ad9850.pde

/*
Simple controller for AD9850 modules
Uses serial protocol (refer to AD9850 datasheet what pins need to be pulled up/down
Uses library by Elecfreaks http://elecfreaks.com/store/download/datasheet/breakout/DDS/EF_AD9850_library.zip
(for use with chipkit delete that unnecessary line "#include <avr/pgmspace.h>" from .h file)
Fix the pin numbers used to communicate with module
Serial comms - 9600, NewLine (0x0A) denotes end of input,
f 10000 - set frequency
s 20 20000 10 1000 - sweep from frequency to frequency using this step size in that many milliseconds
o 10 10000 5 3000 - oscillating sweep from frequency to frequency and back using this step size in that many ms
NB! no error checking in input, code relies on intelligence of user
*/
#include <EF_AD9850.h>
#define MAXBUF 40

// FIXME set up pins to match your case
// parameters in following order - CLK, FQUP, RESET, DATA
EF_AD9850 AD9850(11, 10, 8, 9);
double freqValue = 0;
double freqStart = 0;
double freqEnd = 0;
double freqStep = 0;
int sweepDelay = 0;
char freqStr[MAXBUF];
int bufPos = 0;
char byteIn = 0;
int mode = 0;

void setup()
{
  AD9850.init();
  AD9850.reset();
  Serial.begin(9600);
  memset(freqStr,0,sizeof(freqStr));
}

void loop()
{
  if (mode == 1 || mode == 2)
  {
    delay(sweepDelay);
    if (((freqStep > 0.0) && (freqValue + freqStep <= max(freqStart,freqEnd))) || ((freqStep < 0.0) && (freqValue + freqStep >= min(freqStart,freqEnd))))
      freqValue += freqStep;
    else
      if (mode == 1)
        freqValue = freqStart;
      else
      {
        freqStep *= -1;
        freqValue += freqStep;
      }
    AD9850.wr_serial(0,freqValue);
  }
  while (Serial.available())
  {
    byteIn = Serial.read();
    if (bufPos < sizeof(freqStr))
      freqStr[bufPos++] = byteIn;
    else
      {
        bufPos = 0;
        byteIn = 0;
        memset(freqStr,0,sizeof(freqStr));
        Serial.println("Command too long. Ignored.");
      }
  }
  if (byteIn == 0x0a)
  {
    switch (freqStr[0])
    {
      case 'f':
        mode = 0;
        freqValue = strtod(freqStr+2,NULL);
        freqEnd = 0;
        freqStep = 0;
        sweepDelay = 0;
        Serial.print("Frequency ");
        Serial.println(freqValue);
        break;
      case 's':
      case 'o':
        char *fEnd1, *fEnd2;
        freqStart = abs(strtod(freqStr+2,&fEnd1));
        freqEnd = abs(strtod(fEnd1,&fEnd2));
        freqStep = abs(strtod(fEnd2,&fEnd1));
        if (freqStep == 0)
        {
          Serial.println("You gotta be kidding me, step can not be 0");
          break;
        }
        sweepDelay = abs(atoi(fEnd1));
        if (freqStr[0] == 's')
        {
          mode = 1;
          Serial.print("Sweep");
        }
        else
        {
          mode = 2;
          Serial.print("Oscillate sweep");
        }
        Serial.print(" start freq. ");
        Serial.print(freqStart);
        Serial.print(" end freq. ");
        Serial.print(freqEnd);
        Serial.print(" step ");
        Serial.print(freqStep);
        Serial.print(" time ");
        Serial.println(sweepDelay);
        sweepDelay /= abs(freqEnd - freqStart) / freqStep;
        if (mode == 2)
          sweepDelay /= 2;
        if (freqStart > freqEnd)
          freqStep *= -1;
        freqValue = freqStart;
        break;
      default:
        Serial.println("AI blown up - unknown command");
    }
    memset(freqStr,0,sizeof(freqStr));
    byteIn = 0;
    bufPos = 0;
    AD9850.wr_serial(0,freqValue);
  }
}