HRPWM for for hi-res duty and period control in up-down count (symmetric) mode

Lori Heustess

Other Parts Discussed in Thread: CONTROLSUITE

Engineer Question:

What is the proper way to configure the HRPWM for hi-res duty and period control in up-down count (symmetric) mode? (Piccolo and newer devices)

Answer:

The following provides all the steps necessary to correctly configure the PWM module/s for hi-res duty and period control in up-down count mode. Failure to follow this procedure can result in unpredictable behavior.

// Disable TBCLKSYNC
    EALLOW;
            SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0;     
    EDIS;
 
//Write To CMP, TBPRD, TBPHS registers.
    (*ePWM[j]).TBCTL.bit.PRDLD = TB_SHADOW;             // set Shadow load
    (*ePWM[j]).TBPRD = period;                                         // PWM frequency = 1/(2*TBPRD)
    (*ePWM[j]).CMPA.half.CMPA = period / 2;                   // set duty 50% initially
    (*ePWM[j]).CMPA.half.CMPAHR = (0 << 8);                 // initialize HRPWM extension
    (*ePWM[j]).TBPHS.all = 0;
 
//Configure modes, clock dividers and action qualifier
    (*ePWM[j]).TBCTR = 0;
    (*ePWM[j]).TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN;     // Select up-down count mode
    (*ePWM[j]).TBCTL.bit.SYNCOSEL = TB_SYNC_DISABLE;      
    (*ePWM[j]).TBCTL.bit.HSPCLKDIV = TB_DIV1;
    (*ePWM[j]).TBCTL.bit.CLKDIV = TB_DIV1;                             // TBCLK = SYSCLKOUT
    (*ePWM[j]).TBCTL.bit.FREE_SOFT = 00;
 
    (*ePWM[j]).CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;      // LOAD CMPA on CTR = 0
    (*ePWM[j]).CMPCTL.bit.LOADBMODE = CC_CTR_ZERO;        
    (*ePWM[j]).CMPCTL.bit.SHDWAMODE = CC_SHADOW;
    (*ePWM[j]).CMPCTL.bit.SHDWBMODE = CC_SHADOW;
 
    (*ePWM[j]).AQCTLA.bit.CAU = AQ_SET;                 
    (*ePWM[j]).AQCTLA.bit.CAD = AQ_CLEAR;
    (*ePWM[j]).AQCTLB.bit.ZRO = AQ_SET
    (*ePWM[j]).AQCTLB.bit.PRD = AQ_CLEAR;
   
//Configure HRPWM registers
    EALLOW;
     (*ePWM[j]).HRCNFG.all = 0x0;
     (*ePWM[j]).HRCNFG.bit.EDGMODE = HR_BEP;                      // MEP control on both edges
     (*ePWM[j]).HRCNFG.bit.CTLMODE = HR_CMP;                      // CMPAHR and TBPRDHR HR control
     (*ePWM[j]).HRCNFG.bit.HRLOAD  = HR_CTR_ZERO_PRD;    // load on CTR = 0 and CTR = TBPRD
     (*ePWM[j]).HRCNFG.bit.AUTOCONV = 1;                               // Enable autoconversion
     (*ePWM[j]).HRPCTL.bit.HRPE = 1;                                         // Turn on high-resolution period control
 
//set TBCTL[PHSEN] = 1
     (*ePWM[j]).TBCTL.bit.PHSEN = 1;
 
//set HRPCTL[TBPHSHRLOADE] = 1
     (*ePWM[j]).HRPCTL.bit.TBPHSHRLOADE = 1;
    
//Do the same to all other PWM modules
…
 
//Enable TBCLKSYNC
     SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1;                         
 
//Perform a software sync 
     EPwm1Regs.TBCTL.bit.SWFSYNC = 1;                
…
//Disable TBCTL[PHSEN] and HRPCTL[TBPHSHRLOADE] if not needed by the application code

over 11 years ago

Fernando Chierchie over 11 years ago

Prodigy 95 points

Hi,

Is it possible to use the HRPWM with up/down count mode in F28335 DSP?.

There are some registers that you are setting-up in your code and they are not available in the F28335.

thank in advance.

Fernando.

Hrishi Nene over 11 years ago in reply to Fernando Chierchie

TI__Genius 10820 points

Hi Fernando,

It is possible to use HRPWM in up-down count mode on F28335 devices. However, unlike Piccolo devices, high resolution period control is not possible.

- Hrishi

Edwin.Liu over 10 years ago

Intellectual 600 points

Mark.

Thank you.

Tien Truong DUc over 8 years ago

Intellectual 615 points

Hi Lori Heustess,

I want to configure the HRPWM for hi-res duty and period control in up-down count (symmetric) mode for ePWM1,3,4,5, the duty cycles and period are updated by CLA_task, I try to implement it as following (in .cla file):

#include "SFO_V6.h"

#pragma DATA_SECTION(status,"ClaDataRam0");
volatile Uint16 status;
#pragma DATA_SECTION(MEP_ScaleFactor,"ClaDataRam0");
volatile int MEP_ScaleFactor;

//in CLA_task:
status = SFO();
EPwm1Regs.TBPRD = PRD_INT;
EPwm3Regs.TBPRD = PRD_INT;
EPwm4Regs.TBPRD = PRD_INT;
EPwm5Regs.TBPRD = PRD_INT;
EPwm1Regs.TBPRDHR = PRD_FRAC*256;
EPwm3Regs.TBPRDHR = PRD_FRAC*256;
EPwm4Regs.TBPRDHR = PRD_FRAC*256;
EPwm5Regs.TBPRDHR = PRD_FRAC*256;

I got #17003-D and #10015-D output file......... errors, could you tell me how to fix it? and whether SFO() can use in CLA_task? And how to implement its?

Thank you!

Subrahmanya over 8 years ago in reply to Tien Truong DUc

TI__Mastermind 24095 points

Tien,
Suggested response at,
e2e.ti.com/.../1615041
Further questions can be addressed in the above link.

Tien Truong DUc over 8 years ago in reply to Subrahmanya

Intellectual 615 points

I am using HRPWM (of F28035) for controlling the DC/DC converter with period and duty variable (f=80-250kHz), but my converter had broken when I enabled HRPWM mode, whether HRPWM is resonable for this applications?

Could I use DB submode for deatime setting for multichanels HRPWM?

And if I force HRPWM chanels synchronous through SWFSYNC bit, whether deadtime is guaranteed?

Thank you!

Pierre Bouchet1 over 8 years ago

Expert 2545 points

Hello Lori,

Do you have a similar sample code for an ePWM in up-count (asymetric) mode? Or is up-down-count the only mode where you can adjust both the duty cycle and the period using the HRPWM?

Cheers,

Pierre

Subrahmanya over 8 years ago in reply to Pierre Bouchet1

TI__Mastermind 24095 points

Hi Pierre,

I don't think there are ready examples in controlSuite for this config.
Did you try configuring based on TRM instructions? Did you run into any issues?

-Bharathi.

Pierre Bouchet1 over 8 years ago in reply to Subrahmanya

Expert 2545 points

Hi Bharathi,

I'm sorry, I don't know what you mean by TRM. I've read the datasheet with attention and tried various configurations. I managed to control either the duty cycle or the period in up-count mode, but not both at the same time.

Pierre

Subrahmanya over 8 years ago in reply to Pierre Bouchet1

TI__Mastermind 24095 points

Pierre,

Can you share your EPWM configuration? You should be able to modulate duty and period in both Up-count and Up-Down count modes.

-Bharathi

Subrahmanya over 8 years ago in reply to Subrahmanya

TI__Mastermind 24095 points

Also, Do you have it working in up-down count mode already?

Pierre Bouchet1 over 8 years ago in reply to Subrahmanya

Expert 2545 points

Bharathi,

I already have it working in up-down-count using the sample code given above.

I'm trying to start from there to get up-count to work. I use the same code with only two differences:

EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP;
EPwm1Regs.AQCTLA.bit.CAU = AQ_TOGGLE;

Pierre

C2000™︎ microcontrollers

C2000 microcontrollers forum

HRPWM for for hi-res duty and period control in up-down count (symmetric) mode