general.h

AN1083, Sensorless BLDC Control with Back-EMF Filtering

#include <p30f6010a.h>

// processor frequency using external 7.372 MHz crystal with 16x PLL
#define	FCY		29490000UL

// pwm frequency
#define	FPWM	20000

// FULL_DUTY the equivalent of 100% duty cycle
#define	FULL_DUTY (2*FCY/FPWM)

// Timer 1,2, and 3 prescaler
#define TMR1_PRESCALER 8UL

// Specify the maximum number of degrees of phase advance
#define MAX_PHASE_ADVANCE 30

// Filter phase delay is the delay in the filtered signal compared to the actual signal
// FILTER_PHASE_DELAY is equal to the Group Delay (as a function of filtered signal frequency)
//  multiplied by Fcy divided by the Timer 1 prescaler.
// Assuming a maximum speed of 100000 electrical revs per minute the frequency we are concerned 
//  with is 1666 revs per second.  This is the frequency of the filtered signal this speed
// Refering to the group delay plot in the dsPIC Filter design tool the delay at 1333 Hz
//  is approx 90 us.  At a frequency of 0 the phase delay is 85us.  We can ignore the 5us
//  and just account for the worst case scenerio
// FILTER_PHASE_DELAY = 90us*FCY/TMR1_PRESCALER
#define INVERSE_GROUP_DELAY 11111 // 1/(90us)  
#define FILTER_PHASE_DELAY FCY/TMR1_PRESCALER/INVERSE_GROUP_DELAY

// time through ADC interrupt divided by prescaler
#define PROCESSING_DELAY 410/TMR1_PRESCALER

// time through ADC interrupt divided by prescaler for high speed mode
#define PROCESSING_DELAY_HS 270/TMR1_PRESCALER

// ADC Configuration Values for low and high speed modes
#define ADCON2_LOW_SPEED 0x0410     // channel scan for CH0, MUX A only, 5 conversions per interrupt, Vrefs are AVdd and AVss
#define ADCON2_HIGH_SPEED 0x0408    // channel scan for CH0, MUX A only, 3 conversions per interrupt, Vrefs are AVdd and AVss
#define ADCSSL_LOW_SPEED 0x7880     // scan AN7, AN11, AN12, AN13 and AN14
#define ADCSSL_HIGH_SPEED 0x1880    // scan AN7, AN11, AN12

// Define the ADC result buffers for the analog pins
#define POTBUF	ADCBUF0		//AN7
#define VBUSBUF	ADCBUF1		//AN11
#define VPHABUF	ADCBUF2		//AN12
#define VPHBBUF	ADCBUF3		//AN13
#define VPHCBUF ADCBUF4		//AN14

// PID Speed Control Loop enable.  
// Uncomment this define statement if the user desires that the PID Speed Control Loop be enabled
#define PID_SPEED_LOOP