mic-jammer-ad9833.ino-bkp26032023

/*
    wearable microphone jammer
	
    Version based on original concept &  development :
    https://github.com/y-x-c/wearable-microphone-jamming
	
    Boards needed : 
    Arduino Pro Mini/Micro
    AD9833 signal generator board
    PAM8403 or better - audio amplifier module + potentiometer

    CONNECTION
    --------
    AD9833 PCB to Arduino Pro Mini:
    SDATA --> pin 11 MOSI [note: pin 12 is MISO]
    SCLK --> pin 13 SCK
    FSYNC --> pin 14 A0 (as AD9833 SS)
    DGND --> GND
    VCC --> VCC

    AD9833 PCB to PAM8403 audio amplifier
    AOUT --> LEFT AUDIO IN + RIGHT AUDIO IN
    AGND --> AUDIO GND
	
    Remember to power all boards from +5V/GND lines
	
    AD8933 code borrowed from Tuomas Nylund function generator project :
    https://github.com/tuomasnylund/function-gen
		
*/

#include <Arduino.h>
#include <SPI.h>

// Definition of FSYNC , CHIP SELECT pin in Arduino board
#define FNC_PIN A0

/** \name AD9833 waveform output modes
 * Parameters of \ref ad9833_set_mode()
 * @{
 */
#define AD_OFF      0
#define AD_TRIANGLE 1
#define AD_SQUARE   2
#define AD_SINE     3
/**@}*/

/** \name AD9833 command register bits
 * @{
 */

#define AD_B28     13
#define AD_HLB     12
#define AD_FSELECT 11
#define AD_PSELECT 10
#define AD_RESET   8
#define AD_SLEEP1  7
#define AD_SLEEP12 6
#define AD_OPBITEN 5
#define AD_DIV2    3
#define AD_MODE    1

/** @}*/

/** \name AD9833 register addresses
 * @{
 */
#define AD_FREQ0  (1<<14)
#define AD_FREQ1  (1<<15)
#define AD_PHASE0 (3<<14)
#define AD_PHASE1 ((3<<14)|(1<<13))

/** @}*/

/** \name AD9833 calculation macros
 * @{ */
#define AD_F_MCLK 25000000 ///<Clock speed of the ad9833 reference clock
#define AD_2POW28 268435456 ///<used in calculating output freq

/** Macro that calculates the value for a ad9833 frequency register from a frequency */
#define AD_FREQ_CALC(freq) (uint32_t)(((double)AD_2POW28/(double)AD_F_MCLK*freq)*4)

/** Macro that calculates value for Timer1 output compare from a frequency*/
#define AD_MOD_FREQ_CALC(freq) (F_CPU/(64*(uint32_t)freq))

/** Macro that calculates the value for a ad9833 phase register from a phase in degrees */
#define AD_PHASE_CALC(phase_deg) (uint16_t)((512*phase_deg)/45)
/** @} */

/** Struct that holds all the configuration it's initialized as a global variable
 * in the ad9833.c file */
typedef struct {
    float    freq[2]; ///<Holds the frequencies of 
    float    phase[2];
    float    mod_freq;
    uint8_t  freq_out;
    uint8_t  phase_out;
    uint8_t  mode;
    uint16_t command_reg;
} ad9833_settings_t;


ad9833_settings_t ad_settings; ///<This is used to store all settings.


/**
 * a wrapper function for sending 16-bit SPI packets.
 * \param packet 16-bit value to be sent over SPI.
 */
static inline void ad9833_send(uint16_t packet)
{

  digitalWrite(FNC_PIN,LOW);   // FNCpin low to write to AD9833 over SPI 

  //delayMicroseconds(2); // Some delay may be needed

  // TODO: Are we running at the highest clock rate?
  SPI.transfer((uint8_t)(packet>>8));  // Transmit 16 bits 8 bits at a time
  SPI.transfer((uint8_t)packet);

  digitalWrite(FNC_PIN,HIGH);    // Write to SPI done - bring up this pin
}



/**
 * Initializes the AD9833 and the relevant variables.
 */

void ad9833_init(void)
    {

    // set half awake state
    ad9833_send((1<<AD_SLEEP12)|(1<<AD_RESET));
    ad_settings.command_reg |= (1<<AD_SLEEP12);

    //set some nice default values
    ad9833_set_frequency(0, 0);
    ad9833_set_frequency(1, 0);
    ad9833_set_phase(0, 0);
    ad9833_set_phase(1, 0);
    ad9833_set_freq_out(0);
    ad9833_set_phase_out(0);

}


/** 
 * Sets the ad9833 output waveform to the one given as a parameter.
 * \param mode possible values:
 *      - AD_OFF
 *      - AD_TRIANGLE
 *      - AD_SQUARE
 *      - AD_SINE
 */
void ad9833_set_mode(uint8_t mode){
    ad_settings.mode = mode;
    switch (mode){
        case AD_OFF:
            ad_settings.command_reg |= (1<<AD_SLEEP12);
            ad_settings.command_reg |= (1<<AD_SLEEP1);
            break;
        case AD_TRIANGLE:
            ad_settings.command_reg &= ~(1<<AD_OPBITEN);
            ad_settings.command_reg |=  (1<<AD_MODE);
            ad_settings.command_reg &= ~(1<<AD_SLEEP12);
            ad_settings.command_reg &= ~(1<<AD_SLEEP1);
            break;
        case AD_SQUARE:
            ad_settings.command_reg |=  (1<<AD_OPBITEN);
            ad_settings.command_reg &= ~(1<<AD_MODE);
            ad_settings.command_reg |=  (1<<AD_DIV2);
            ad_settings.command_reg &= ~(1<<AD_SLEEP12);
            ad_settings.command_reg &= ~(1<<AD_SLEEP1);
            break;
        case AD_SINE:
            ad_settings.command_reg &= ~(1<<AD_OPBITEN);
            ad_settings.command_reg &= ~(1<<AD_MODE);
            ad_settings.command_reg &= ~(1<<AD_SLEEP12);
            ad_settings.command_reg &= ~(1<<AD_SLEEP1);
            break;
    }
    ad9833_send(ad_settings.command_reg);
}


/**
 * Selects which frequency register is used to generate the output.
 * Also used to select FSK.
 * \param phase_out possible values:
 *      - 0 = use phase register 0
 *      - 1 = use phase register 1
 *      - 2 = PSK
 */
void    ad9833_set_freq_out(uint8_t freq_out){
    ad_settings.freq_out = freq_out;
    switch (freq_out){
        case 0:
            ad_settings.command_reg &= ~(1<<AD_FSELECT);
            break;
        case 1:
            ad_settings.command_reg |= (1<<AD_FSELECT);
            break;
        case 2:
            //TODO
            break;
    }
    ad9833_send(ad_settings.command_reg);
}


/**
 * sets the desired ad9833 internal phase register to a value that
 * produces the desired phase.
 *
 * \param reg the desired phase register to be manipulated, either 0 or 1
 * \param phase the desired phase
 */
void ad9833_set_phase(uint8_t reg, double phase){
    uint16_t reg_reg; //probably should be renamed...
    if (reg==1)
        reg_reg = AD_PHASE1;
    else
        reg_reg = AD_PHASE0;

    ad_settings.phase[reg] = phase;

    ad9833_send(reg_reg | AD_PHASE_CALC(ad_settings.phase[reg]));

}

/**
 * Selects which phase register is used to generate the output
 * Also used to select PSK
 * \param phase_out possible values:
 *  - 0 = use phase register 0
 *  - 1 = use phase register 1
 *  - 2 = PSK
 */
void    ad9833_set_phase_out(uint8_t phase_out){
    ad_settings.phase_out = phase_out;
    switch (phase_out){
        case 0:
            ad_settings.command_reg &= ~(1<<AD_PSELECT);
            break;
        case 1:
            ad_settings.command_reg |= (1<<AD_PSELECT);
            break;
        case 2:
            //TODO
            break;
    }
    ad9833_send(ad_settings.command_reg);
}


/**
 * sets the desired ad9833 internal frequency register to a value that
 * produces the desired frequency.
 *
 * \param reg the desired frequency register to be manipulated, either 0 or 1
 * \param freq the desired frequency
 */
void ad9833_set_frequency(uint8_t reg, double freq){
    uint32_t freq_reg;
    uint16_t reg_reg; //probably should be renamed...
    freq_reg = AD_FREQ_CALC(freq);
    ad_settings.freq[reg] = freq;

    if (reg==1)
        reg_reg = AD_FREQ1;
    else
        reg_reg = AD_FREQ0;

    ad9833_send((1<<AD_B28) | ad_settings.command_reg);
    ad9833_send(reg_reg | (0x3FFF&(uint16_t)(freq_reg>>2 )));
    ad9833_send(reg_reg | (0x3FFF&(uint16_t)(freq_reg>>16)));

}




// -----------------------------------------------------------------------
//      MAIN CODE OF THE JAMMER 
// -----------------------------------------------------------------------


void setup() 
  {
  //initializing SPI and AD9833 generator
  pinMode(FNC_PIN,OUTPUT);
  digitalWrite(FNC_PIN,HIGH);   

  SPI.begin();

   //We set the mode here, because other hardware may be doing SPI also
  SPI.setDataMode(SPI_MODE2);
  
  delay(100);
  ad9833_init();
  delay(15);

  //set gen to SINE
  ad9833_set_mode(AD_SINE);
  ad9833_set_frequency(0, 25000);
}

void loop() {
  ad9833_set_mode(AD_SINE);
  ad9833_set_frequency(0, random(24000, 26000) );
}