F4GOJ Christophe [email protected]

August 2014

AD9850 datasheet at http://www.analog.com/static/imported-files/data_sheets/AD9850.pdf

Use this library freely.

To use the AD9850 library:

• Go to https://github.com/F4GOJ/AD9850, click the Download ZIP button and save the ZIP file to a convenient location on your PC.
• Uncompress the downloaded file. This will result in a folder containing all the files for the library, that has a name that includes the branch name, usually AD9850-master.
• Rename the folder to AD9850.
• Copy the renamed folder to the Arduino sketchbook\libraries folder.

The AD9850 library instantiates a DDS object, the user does not need to do this.

#include <AD9850.h>    //http://github.com/F4GOJ/AD9850

• W_CLK -> any pin
• FQ_UD -> any pin
• DATA/D7 -> any pin
• RESET -> any pin

Initialize the output pins and master reset the AD9850

DDS.begin(w_clk, fq_ud, data, reset);

w_clk : Working clock output pin, any pin (int)
fq_ud : Frequency update pin, any pin. (int)
data : Serial data output pin, any pin (int)
reset : Reset output pin, any pin. (int)

None.

void setup(){
 DDS.begin(6, 7, 8, 9);
}

Compensation of crystal oscillator frequency.
Can be used at any time after initialization.

DDS.calibrate(trim_freq);

trim_freq : Adjust around 125000000 to match the real crystal oscillator frequency. (double)

None.

void setup(){
 DDS.begin(6, 7, 8, 9);
}

void loop(){
 DDS.calibrate(124999000);
}

Sets the output frequency of the AD9850 and the phase of the signal.

DDS.setfreq(frequency, phase);

frequency : Output frequency in Hz. (double)
phase : Sets the phase of the output signal, coded on 5 bits allows 32 phase steps of 11,25° each. (int)

None.

double frequency = 10000000;
int phase = 0;
DDS.setfreq(frequency, phase);

Power down mode reducing the dissipated power from 380mW to 30mW at 5V

DDS.down();

None.

None.

DDS.down();

Wakes-up the AD9850 from power down mode.

DDS.up();

None.

None.

DDS.down(); // Entering power down mode

// some code doing something

...

DDS.up(); // WAKE-UP !!! :)