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 13 years ago

Fernando Chierchie over 12 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 12 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 11 years ago

Intellectual 600 points

Mark.

Thank you.

Tien Truong DUc over 10 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 10 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 10 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 10 years ago

Expert 2595 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 10 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 10 years ago in reply to Subrahmanya

Expert 2595 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 10 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 10 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 10 years ago in reply to Subrahmanya

Expert 2595 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