How to turn off the autoresonance on the DRV2603?

Hi, Charles:

I looked into the firmware of DRV2603EVM-CT. the auto-resonance-off state is a fake state.

here is the detail:

when we enter the auto-resonance off mode:

    case BUTTON2:
    {
     Haptics_SendWaveform(lra_alert_dumb); // LRA alert with auto-resonance off
     break;
    }

// Waveform Structure Type Definition

typedef struct Haptics_Waveform {  

const unsigned char  outputMode;   // ERM, LRA_AUTOON, or LRA_AUTOOFF (see output modes above)  

const unsigned char  length;    // size of array in bytes  

const unsigned char*  data;    // pointer to waveform array data (waveform array is in (amplitude, time) pairs

} Waveform;

const Waveform lra_alert_dumb = {LRA_AUTOOFF,4,lra_alert_dumb_data};

void Haptics_SendWaveform(const Waveform waveform)

{  

if(playEffect)  {   

Haptics_HardwareMode(waveform.outputMode); // Set hardware control pins   

Haptics_StartPWM();       // Start PWM output

  Haptics_OutputWaveform(waveform);   // Control the PWM or I2C

  Haptics_StopPWM();   // Stop PWM output  

}

}

void Haptics_HardwareMode(uint8_t outputMode)
{
 switch(outputMode)
 {
 case LRA_AUTOON:  // LRA with Auto-Resonance
  P3OUT |= 0x01;      // Select LRA Mode on DRV2603
  P2OUT |= 0x40;      // Select LRA on Load Switch
  break;
 case LRA_AUTOOFF:  // LRA without Auto-Resonance
  P3OUT &= 0xFE;      // Select ERM Mode on DRV2603
  P2OUT |= 0x40;      // Select LRA on Load Switch
  break;
 case ERM:    // ERM Mode
  P3OUT &= 0xFE;      // Select ERM Mode on DRV2603
  P2OUT &= 0xBF;      // Select ERM on Load Switch
  break;
 default:   // LRA with Auto-resonance
  P3OUT |= 0x01;      // Select LRA Mode on DRV2603
  P2OUT |= 0x40;      // Select LRA on Load Switch
  break;
 }
}

void Haptics_OutputWaveform(const Waveform waveform) {  

switch(waveform.outputMode)  {  

case LRA_AUTOON:  // LRA with Auto-Resonance   

for(k=0; k < waveform.length; k=k+2)   {   

 if(waveform.data[k] == 0x80)     

P3OUT &= 0xFD;                 //Disable Amplifier    

else     

P3OUT |= 0x02;             //Enable Amplifier, Start PWM

         TA1CCR1 = waveform.data[k];     //Waveform*1.625   

         for(j=0;j<waveform.data[k+1];++j)    {     timerdelay(Haptics_resonantModeTick);    }   }  

 break;  

case LRA_AUTOOFF:  // LRA without Auto-Resonance  

 for(k=0; k<waveform.length; k=k+2)   {   

 if(waveform.data[k] == 0x80)     

P3OUT &= 0xFD;                 //Disable Amplifier    

else     P3OUT |= 0x02;             //Enable Amplifier, Start PWM

         for(j=0;j<waveform.data[k+1];++j)    {     

TA1CCR1 = waveform.data[k];     

timerdelay(Haptics_dumbModeTick);     

TA1CCR1 = 255 - waveform.data[k];    

 timerdelay(Haptics_dumbModeTick);    

}   

}   

break;  

case ERM:  // ERM   

for(k=0; k<waveform.length; k=k+2)   {    

TA1CCR1 = waveform.data[k];     //Waveform*1.625    

for(j=0;j<waveform.data[k+1];++j)   

 {     timerdelay(Haptics_resonantModeTick);    }  

 }   

break;  

}

}