/*
Version 1 10 February,2015 ND6T
This source file is under General Public License version 3.0
Control of AD9850 DDS board by Arduino Uno R3 using minimal leads and serial USB control
*/
//Prep for AD9850
#define CLK 10 // Pin 10 : AD9850 clock pin
#define FQ 11 // Pin 11 : freq update pin
#define DAT 12 // Pin 12 : DATA pin
#define RST 13 // Pin 13 - RST
#define pulse(pin) {digitalWrite(pin, HIGH); digitalWrite(pin, LOW); }
void setup() {
// Initialize serial communication at 9600 bits per second:
Serial.begin(9600);
pinMode(FQ, OUTPUT);
pinMode(CLK, OUTPUT);
pinMode(DAT, OUTPUT);
pinMode(RST, OUTPUT);
pulse(RST);
pulse(CLK);
pulse(FQ);
}
void loop() {
// Read the input:
if (Serial.available() > 0) {
float frequency= Serial.parseFloat();
//Confirm input:
Serial.print("Output frequency= ");
Serial.print(frequency);
Serial.println(" Hertz");
// Send it to the AD9850
output(frequency);
}
}
void output(float frequency) {
long freq = frequency * pow (2,32) /125000000; // Reference clock i
for (int b=0; b<4; b++, freq >>= 8) shiftOut(DAT,CLK,LSBFIRST,freq);
shiftOut(DAT,CLK,LSBFIRST,0);
pulse(FQ);
}