CCS/TMS320F28379D: TBCTL.SYNCOSEL, the SYNCSELECT Register, and ePWMx Chain Synchronizing

Graham Reitz29

Part Number: TMS320F28379D

Tool/software: Code Composer Studio

Hello,

A few questions on ePWM synchronization:

1) If the TBCTL.SYNCOSEL bits are set to 0x0 does that mean that no synchronization signal is propagated from that ePWMx unless a TBCTL.SWFSYNC is set?

2) How does the SYNCSELECT related to the TBCTL.SYNCOSEL setting?

3) If SYNCSELECT.EPWM4SYNCIN is set to 0x0 does that mean that the EPWM1SYNCOUT signal will automatically be propagated to ePWM4?

4) If the synchronization chain is configured so that ePWMs 1-3 and ePWMs 4-6 are synchronized will starting the ePWM1 signal automatically start and synchronize the remaining ePWMs to ePWM1?

I'm trying to synchronize ePWMs 2-6 with ePWM1 and have been unable to do so. Presumably I don't understand the synchronization settings.

Thanks in advance for any assistance.

Kindly,

Graham

over 6 years ago

0 Nima Eskandari over 6 years ago

TI__Guru 52040 points

I’ll put the answers together and get back to you.

0 Graham Reitz29 over 6 years ago in reply to Nima Eskandari

Intellectual 960 points

Thanks Nima!

0 Graham Reitz29 over 6 years ago in reply to Nima Eskandari

Intellectual 960 points

Hi Nima,

Have you had a moment to look into my questions?

Thanks,

Graham

0 Nima Eskandari over 6 years ago

TI__Guru 52040 points

1. When SYNCOSEL == 0, that means SWSYNC OR SYNCIN signal are passed to SYNCOUT of each PWM. To disable the SYNCING of the module down the chain, set PHSEN = 0.

2.SYNCSELECT registers are used to configure the muxes for SYNCIN for each PWM at the top of the chain. SYNCOSEL however, decides what signal is used as the SYNCOUT of the EPWM module.

3. YES

4. Depending on what signal is selected to synchronize each PWM. If they are all set to sync on SYNCIN and the EPWM1 SYNCOUT is passed as the SYNCIN for all these modules, then yes. However, if EPWM4 does not use SYNCIN, and the SYNCOUT is set to be signal genereated by EPWM4 and not by just passing EPWM1 SYNCOUT through, then EPWM4-6 are not synced with EPWM1-3

5. Okay to synchronize EPWM2-6 with EPWM1.

Disbale PHSEN for EPWM1.

Enable PHSEN for EPWM2-6.

SET EPWM1 SYNCOSEL to PRD/ZERO

Set EPWM2-6 SYNCOSEL to SYNCIN (to pass EPWM1 SYNCOUT through)

Configure SYNCSEL.EPWM4SYNCIN to use EPWM1 SYNCOUT.

That should do it :)

0 Graham Reitz29 over 6 years ago in reply to Nima Eskandari

Intellectual 960 points

Awesome. Thank you!

C2000™︎ microcontrollers

C2000 microcontrollers forum

CCS/TMS320F28379D: TBCTL.SYNCOSEL, the SYNCSELECT Register, and ePWMx Chain Synchronizing