C2000 Synchronization of ePWM modules with external signal

Hello everyone, I am trying to use an external signal to synchronize 4 ePWM (ePWM1, ePWM2, ePWM3 and ePWM4) modules together, however I have not been able to make it work. Modules ePWM1, ePWM2 and ePWM3 are configured as UP/DOWN with TBPRD = 5000 (achieving 20 kHz period) and ePWM4 is also configured in UP/DOWN mode, however TBPRD = 50000 (achieving 2 kHz). I would like to use a signal connected to GPIO40 as an external SYNC to the ePWM modules. The signal is 2 kHz. How am I supposed to configure the ePWM Blocks in Simulink??? BTW: I have configured GPIO40 als SYNCI inthe Hardware settings tab.

I have also noticed that Simulink is not setting the EPWMSYNCINSEL register in the generated code.....

I am using a TMS320F28388D ControlCard

Thanks!

Answer 1

[Jiabo]

Hi Roberto

Did you fix this problem? How to cope it?

Answer 2

[MULI]

Hi @Roberto,

To configure ePWM1, ePWM2, ePWM3, and ePWM4 for synchronization using an external signal connected to GPIO40, you can follow these steps:

• In Simulink, go to Hardware Settings and configure GPIO40 as the SYNCI signal.
• Set ePWM1, ePWM2, and ePWM3 to Up/Down Mode with TBPRD = 5000 (20 kHz).
• Set ePWM4 to Up/Down Mode with TBPRD = 50000 (2 kHz).
• Enable Synchronization (TBCTL[SYNCOSEL]) for each ePWM module to allow synchronization via the external input.
• If Simulink does not set EPWMSYNCINSEL = 0x18 (Input X-BAR) in the generated code: Use a custom code block in Simulink to set the register manually in the initialization phase.

EPwmXbarRegs.EPWMSYNCINSEL.bit.SYNCIN = 0x18; // Map Input X-BAR to SYNCI 

You can refer to the below example which demonstrates synchronization of ePWM modules and includes configuration steps which is relevant to your requirements.

https://www.mathworks.com/help/ti-c2000/ug/time-base-counter-synchronization-epwm-example.html