TMS320F280049: C code example of new blanking capability

Hi Holger,

We don't have a blanking window example. However, it's really nothing special. From the cmpss's perspective, it's basically a "pwmsync" signal with a configurable pulse that comes from the digital compare submodule of the epwm.

Hello,
is this the same blanking concept as on the F28035? Then I found example code for the TMDSSOLARUINVKIT.

Regards, Holger

Holger,

Our previous devices have had blanking support in the ePWM but TMS320F280049 is our first device in which the blanking signal from the ePWM is sent to the CMPSS.

Hello Frank,
the description of this new PWMxBLANK sync signal in the TRM is not very detailed. May be there can be added some more description in the TRM.

Regards, Holger

Hello Frank,
it would be helpful if you can send me a description of the PWMxBLANK sync signal in advance.

Regards, Holger

Hi Holger,

Since EPWMBLANK doesn't belong to the CMPSS, there won't be a detailed description of it in the CMPSS chapter as this would be just duplicate information from the EPWM chapter. The CMPSS chapter in question will be expanded to something along the lines of the below highlighted. Note that the wording is preliminary and could change slightly.

16.6.1 LATCHCLR, EPWMSYNCO and EPWMBLANK Signals

 

The LATCHCLR signal clears the synchronize block, digital filter and the latch. It is activated in software

using xLATCHCLR(x= “H” or “L”). It can also be activated by EPWMSYNCO when xSYNCCLREN(x= "H"

or "L") is set. If a longer LATCHCLR signal is required, the EPWMBLANK signal can be used to extend it

by setting BLANKEN.

EPWMSYNCO and EPWMBLANK (BLANKWDW) come from the Time-Base and Digital Compare submodules of the EPWM. For a detailed description of how these two signals are generated, refer to the respective submodule chapter of the EPWM.

8640.Doc1.docxHello Frank,

thx for the answer. Still customer has some questions:

- It is not clear which signal is referred to the PWMBLANK signal

- It is not clear how a edge control signal at the red marks position (see attached) will work.

Regards, Holger

Hi Holger,

It's been a few days since we heard from you. Are you clear on how the blank window operates?

Hello Frank,
they will go on by them own now and will come back if there is something not clear. Please let me know if there is a new TRM with this infos inside.

Regards, Holger

Ok Holger, sounds good. A new TRM will probably be published sometime around mid-year. If it's ok with you, I'm going to mark this thread as resolved. If they come back needing more information, you can reply to this thread or create a new one if this one locks out due to inactivity.