encoder.c

Position PID algorithm control motor by dsPIC

#include "encoder.h"
signed long encoder_value=0;//current value of encoder
signed int encoder_overflow=0;
void ConfigIntQEI(unsigned int config)
{
    _QEIIF = 0;                 /* clear Interrupt flag */
    _QEIIP = config & 0x07;     /* bits <2:0> is the priority*/
    _QEIIE = (config & 0x8)>>3; /* bit 3 is interrupt enable/diable */
}

void CloseQEI(void)
{
    _QEIIE = 0;     /* disable interrupt */
    _QEIM = 0x0;    /* QEI/Timer off */  
    _QEIIF = 0;     /* clear IF flag */
}

//unsigned int ReadQEI(void)
//{
//    return POSCNT;  /* return the current position count */
//}


//void WriteQEI(unsigned int position)
//{
//    MAXCNT = position;  /* set the Maxium Count */
//}

//void OpenQEI(unsigned int config1, unsigned int config2)
//{
    /* clear CNTERR bit */
//    QEICONbits.CNTERR = 0;
	
    /* configures the QEI/Timer */
//    QEICON = config1 & 0x2fff;

//    QEICONbits.UPDN = config1 >>11; /* assign up/down  */

    /* configures the Digital Filters */
//    DFLTCON = config2;
//}

void QEI_init(void)
{
	CloseQEI();
	ADPCFG |= 0x0030;// Configure QEI pins as digital inputs

	QEICONbits.QEIM = 0;// Disable QEI Module
	ConfigIntQEI(QEI_INT_PRI_1 & QEI_INT_ENABLE);//
	//ConfigIntQEI(QEI_INT_DISABLE);// disable interrupt
    POSCNT  = ENCODER_ZERO_VALUE;//initial value of encoder
    MAXCNT = 0xFFFF;//max value of POSCNT
/* configures the QEI/Timer : QEICON*/
    QEICONbits.CNTERR = 0;//clear CNTERR bit
	QEICONbits.QEISIDL =1;//Stop in Idle Mode
	//QEICONbits.INDX : read only output pin	
	//QEICONbits.UPDN = 1;//1 = Position Counter Direction is positive (+)
						  //become read only when QEIM=1xx
	
	
					//	 with position counter reset by match (MAXCNT)
	QEICONbits.SWPAB=0;// Phase A and Phase B Input not swapped
	//QEICONbits.PCDOUT=0;//Position Counter Direction State Output is disable
						//pin69 UPDN
						//be aware of I/O conflict with CN interrupt

	//QEICONbits.TQGATE=1;//Timer Gated Time Accumulation is enabled
	//QEICONbits.TQCKPS=0b00;//Timer Input Clock Prescale 1:1
	//11 = 1:256 prescale value
	//10 = 1:64 prescale value
    //01 = 1:8 prescale value
	//00 = 1:1 prescale value
	QEICONbits.POSRES=0;//Position Counter Reset is disabled
	//QEICONbits.TQCS=0;//Timer Clock Source Select 
					//0 = Internal clock TCY
	//QEICONbits.UPDN_SRC=0;//Position Counter Direction Selection Control
						//0 = Control/Status bit, UPDN (QEICON<11>)
						// don't care when QEIM=0b111

	/* configures the Digital Filters */
	DFLTCONbits.CEID=1;//Count Error Interrupt is Disabled
	DFLTCONbits.QEOUT=1;//QEA/QEB Digital Filter Output is Enabled
	//DFLTCONbits.QEOUT=0;
	DFLTCONbits.QECK=0b011;//QEA/QEB Digital Filter Clock Divide Select
						//111 = 1:256 Clock Divide
						//110 = 1:128 Clock Divide
						//101 = 1:64 Clock Divide
						//100 = 1:32 Clock Divide
						//011 = 1:16 Clock Divide
						//010 = 1:4 Clock Divide
						//001 = 1:2 Clock Divide
						//000 = 1:1 Clock Divide
	//DFLTCONbits.INDOUT=1;//Index Channel Digital Filter Output Enable
	//DFLTCONbits.INDCK=0b000;//NDCK<2:0>: Index Channel Digital Filter Clock Divide Select	
	DFLTCONbits.IMV=0b00;// Index Match Value