EQEP setup

Dear Manish,

I'm using the following example

controlSUITE\device_support\F2837xD\v100\F2837xD_examples_Cpu1\eqep_pos_speed

I was trying to understand the code and parameter setup but I couldn't follow the line mentioned in my previous post. However, I just found another post which answers my question.

16777=(1/4000)*2^26 and I think 2^26 comes from the IQ library configuration. Sorry this was a  silly question, but it's my first time working with TI devices. But many thanks for your reply.

Hi Manish,

I have TMS320F28335 Experimenter Kit (TMDSDOCK28335). I have PMSM 400 W, 160 V, 1.85 A , 3000 Rpm parameter values and encoder parameters (8P-2500 P/R). 8 refers to pole number. i can not read speed and position with sensorless PMSM program in controlsuit. Integrated encoder with PMSM has (A,A',B,B',Z,Z',U,U',V,V',W,W', +5V, GND) terminals. I connect A,B,I and +5V, GND. I saw changing of QEP register values in wach window while the system works real time. I think i need to change ancoder program. How can i make to change in following code.

Thanks a lot.

/* =================================================================================
File name: F2833XQEP.H
Target : F2833x family
==================================================================================*/

#ifndef __F2833X_QEP_H__
#define __F2833X_QEP_H__

#include "f2833xbmsk.h"
#include "f2833xdrvlib.h"

/*-----------------------------------------------------------------------------
Initialization states for EQEP Decode Control Register
------------------------------------------------------------------------------*/
#define QDECCTL_INIT_STATE ( XCR_X2 + QSRC_QUAD_MODE )

/*-----------------------------------------------------------------------------
Initialization states for EQEP Control Register
------------------------------------------------------------------------------*/
#define QEPCTL_INIT_STATE ( QEP_EMULATION_FREE + \
PCRM_INDEX + \
IEI_RISING + \
IEL_RISING + \
QPEN_ENABLE + \
QCLM_TIME_OUT + \
UTE_ENABLE )

/*-----------------------------------------------------------------------------
Initialization states for EQEP Position-Compare Control Register
------------------------------------------------------------------------------*/
#define QPOSCTL_INIT_STATE PCE_DISABLE

/*-----------------------------------------------------------------------------
Initialization states for EQEP Capture Control Register
------------------------------------------------------------------------------*/
#define QCAPCTL_INIT_STATE ( UPPS_X32 + \
CCPS_X128 + \
CEN_ENABLE )

/*-----------------------------------------------------------------------------
Define the structure of the QEP (Quadrature Encoder) Driver Object
-----------------------------------------------------------------------------*/
typedef struct {_iq ElecTheta; // Output: Motor Electrical angle (Q24)
_iq MechTheta; // Output: Motor Mechanical Angle (Q24)
Uint16 DirectionQep; // Output: Motor rotation direction (Q0)
Uint16 QepPeriod; // Output: Capture period of QEP signal in number of EQEP capture timer (QCTMR) period (Q0)
Uint32 QepCountIndex; // Variable: Encoder counter index (Q0)
int32 RawTheta; // Variable: Raw angle from EQEP Postiion counter (Q0)
_iq MechScaler; // Parameter: 0.9999/total count (Q30)
Uint16 LineEncoder; // Parameter: Number of line encoder (Q0)
Uint16 PolePairs; // Parameter: Number of pole pairs (Q0)
int32 CalibratedAngle; // Parameter: Raw angular offset between encoder index and phase a (Q0)
Uint16 IndexSyncFlag; // Output: Index sync status (Q0)
} QEP;

/*-----------------------------------------------------------------------------
Default initializer for the QEP Object.
-----------------------------------------------------------------------------*/

#define QEP_DEFAULTS { 0x0,0x0,0x0,0x0,0x0,0x0,0x00020000,0x0,2,0,0x0}

/*-----------------------------------------------------------------------------
QEP Init and QEP Update Macro Definitions
-----------------------------------------------------------------------------*/

#define QEP_INIT_MACRO(m,v) \
\
(*eQEP[m]).QDECCTL.all = QDECCTL_INIT_STATE; \
(*eQEP[m]).QEPCTL.all = QEPCTL_INIT_STATE; \
(*eQEP[m]).QPOSCTL.all = QPOSCTL_INIT_STATE; \
(*eQEP[m]).QUPRD = 1500000; /* Unit Timer for 150Hz*/ \
(*eQEP[m]).QCAPCTL.all = QCAPCTL_INIT_STATE; \
(*eQEP[m]).QPOSMAX = 4*v.LineEncoder; \
\

//Make sure that the pin configuration is properly done in ...-DevInit_F2803x.c file like below \
EALLOW; /* Enable EALLOW*/ \
GpioCtrlRegs.GPAMUX2.bit.GPIO20 = 1; /* GPIO20 is EQEP1A */ \
GpioCtrlRegs.GPAMUX2.bit.GPIO21 = 1; /* GPIO21 is EQEP1B */ \
GpioCtrlRegs.GPAMUX2.bit.GPIO23 = 1; /* GPIO23 is EQEP1I */ \
EDIS; /* Disable EALLOW*/

#define QEP_MACRO(m,v) \
\
/* Check the rotational direction */ \
v.DirectionQep = (*eQEP[m]).QEPSTS.bit.QDF; \
\
/* Check the position counter for EQEP1 */ \
v.RawTheta = (*eQEP[m]).QPOSCNT + v.CalibratedAngle; \
\
if (v.RawTheta < 0) \
v.RawTheta = v.RawTheta + (*eQEP[m]).QPOSMAX; \
else if (v.RawTheta > (*eQEP[m]).QPOSMAX) \
v.RawTheta = v.RawTheta - (*eQEP[m]).QPOSMAX; \
\
/* Compute the mechanical angle */ \
v.MechTheta= v.MechScaler*v.RawTheta; \
/* Compute the electrical angle */ \
v.ElecTheta = (v.PolePairs*v.MechTheta) -floor(v.PolePairs*v.MechTheta); /* Q24 = Q0*Q24 */ \
\
/* Check an index occurrence*/ \
if ((*eQEP[m]).QFLG.bit.IEL == 1) \
{ \
v.IndexSyncFlag = 0x00F0; \
v.QepCountIndex = (*eQEP[m]).QPOSILAT; \
(*eQEP[m]).QCLR.bit.IEL = 1; /* Clear interrupt flag */ \
} \
\
/* Check unit Time out-event for speed calculation: */ \
/* Unit Timer is configured for 100Hz in INIT function*/ \
if((*eQEP[m]).QFLG.bit.UTO == 1) \
{ \
/***** Low Speed Calculation ****/ \
if(((*eQEP[m]).QEPSTS.bit.COEF || (*eQEP[m]).QEPSTS.bit.CDEF)) \
{ /* Capture Counter overflowed, hence do no compute speed*/ \
(*eQEP[m]).QEPSTS.all = 0x000C; \
} \
else if((*eQEP[m]).QCPRDLAT!=0xffff) \
/* Compute lowspeed using capture counter value*/ \
v.QepPeriod = (*eQEP[m]).QCPRDLAT; \
}

#endif // __F2833X_QEP_H__

Yeah I found those in project called HVPM_Sensored but there is an error in DMC2833x_DRV.pdf. Because it said that code composer is converting MechScaler in I2Q30 format, but the numbers are wrong because (1/4000)*2^30 its not 16777 rather 268435.456.

Hello user4800014,

I see that you are posting to a thread which has been inactive since 2014. If you have an issue for which you require support, please post a new thread.

Best Regards,
Adam Dunhoft