How can I obtain 12epwm signals from F28379D Launchpad?

I want to see 12 epwm signals on the oscilloscope at the same time using TMS320F28379D launcpad, but Matlab/simulink-2022b does not allow me to use the same epwm block twice. I tried to set epwmA and epwmB using epwm1 block. According to the datasheet, I should have seen pwm from pins 39 and 40. However, I couldn't see it. I would be very happy if you could help.

Answer 1

[Vishwa]

Hi,

You should certainly be able to use multiple ePWM blocks, just make sure that each block is configured to a different ePWM module. TMS320F28379D launchpad has 12 ePWM modules, depending on your requirements you can use either all 12 ePWM blocks or 6 ePWM blocks. (1 block can generate 2 complementary pulses)

GPIO Pins in which you prefer to see the output can be configured from “Model Settings > Hardware Implementation”

For detail description of ePWM block in Simulink please refer the following documentation: Generate enhanced Pulse Width Modulated (ePWM) waveforms - Simulink - MathWorks India

Please see this example, which uses 2 ePWM blocks: Using Time-Base Counter Synchronization to Synchronize ePWMs and eCAPS - MATLAB & Simulink - MathWorks India

Hope it helps!

Regards,

Vishwa

[Merve Aydin]

Thank you for your answer, I am using the block you have given and done all the arrangments in Hardware Implementation as you have shown in the figures (attached as ss11-ss99). The configurations I have done inside the block are given below. I cant seem to obtain 2 epwm signals from a singal block. Have I selected something wrong? Can you send me the seletions I should do to obtain 2 epwm signals from just one block. Thank you for your time.

[Vishwa]

Attached here is a working Simulink model for your reference. In this model I am using ePWM block, where CMPA and CMPB values are given via input port. On the launchpad I have shorted GPIO 0 (ePWM A) with GPIO 14 and GPIO 1 (ePWM B) with GPIO 15. GPIO 14 and 15 are configured as input pins which can be observed in SImulink via "Monitor and Tune".

For info on "Monitor and Tune" please refer: Signal Monitoring and Parameter Tuning over XCP on Serial - MATLAB & Simulink - MathWorks India

Few suggestions to keep in mind:

1. Make sure external reference signals are within the limits of Up/Down counter time period.
2. Check whether Simulink is able to deploy the generated embedded code to the target. COM Port should not be used by some other software, such as CCS.
3. Try increasing the prescaler divider values.

I hope this resolves your problem.

Regards,

Vishwa

[Merve Aydin]

Can you re-attach this .slx file in 2022b format? thank you very much for your time

[Vishwa]

Here is the same Simulink model compatible with R2022b.

[Merve Aydin]

I am sincerely grateful

[Merve Aydin]

Hello again Vishwa,

I have another question, I tried obtaining SPWM with the blocks you sent me last time. I want to change the ePWM trigger as it is in the attached file I'm sending. I couldn't find where to change the form of the trigger signal inside the block. Do you have any suggestions?

Thank you for your time,

Best regards...