TMS320F28388D: CLB module and ePWM module output association

user6101616

Part Number: TMS320F28388D
Other Parts Discussed in Thread: C2000WARE

Hello，

I found a problem, but I don't understand why. I didn't find the answer in the TRM.

The ePWM1 moudle route to two pairs of pins, one pair of GPIO0 and GPIO1, another pair of GPIO145 and GPIO146, when these two sets of pins are associated with CLB output, I find some differences：

The EPWM1 route to GPIO 0 and GPIO1 as follow，the output of CLB is OK, and the oscilloscope can capture the CLB output from gpio0 and gpio1

GPIO_setPinConfig(GPIO_0_EPWM1A);
GPIO_setDirectionMode(0, GPIO_DIR_MODE_OUT);
GPIO_setPadConfig(0, GPIO_PIN_TYPE_STD);

    GPIO_setPinConfig(GPIO_1_EPWM1B);
    GPIO_setDirectionMode(1, GPIO_DIR_MODE_OUT);
    GPIO_setPadConfig(1, GPIO_PIN_TYPE_STD);

CLB_setOutputMask(CLB1_BASE, 1 << 0 | 1 << 2, true);

But when EPWM1 route to GPIO145 and GPIO146, there is no output from CLB, and the oscilloscope can't see anything from these two pins

GPIO_setPinConfig(GPIO_145_EPWM1A);
GPIO_setDirectionMode(145, GPIO_DIR_MODE_OUT);
GPIO_setPadConfig(145, GPIO_PIN_TYPE_STD);

    GPIO_setPinConfig(GPIO_146_EPWM1B);
    GPIO_setDirectionMode(146, GPIO_DIR_MODE_OUT);
    GPIO_setPadConfig(146, GPIO_PIN_TYPE_STD);

CLB_setOutputMask(CLB1_BASE, 1 << 0 | 1 << 2, true);

Is this right？

Thank you！ Hope for your reply.

over 4 years ago

0 Subrahmanya over 4 years ago

TI__Mastermind 24095 points

Hi,

Do you see normal PWM output when it's mapped to GPIO145 and GPIO146 and CLB is not used?

I do not expect the behavior to be different based on where PWM is mapped. I'll check and get back to you.

0 user6101616 over 4 years ago in reply to Subrahmanya

Intellectual 320 points

When not related to CLB, the outputs of these two pins are normal. So I was confused

0 Subrahmanya over 4 years ago in reply to user6101616

TI__Mastermind 24095 points

Hi,

Thanks for confirming. We are checking this and we'll get back to you later this week.

0 Subrahmanya over 4 years ago in reply to Subrahmanya

TI__Mastermind 24095 points

Hi,

I could replicate what you've observed. I do not see activity on GPIO145 when i select CLB enabled function on that pin.
I'll check with the design team and confirm and update the documentation or errata if this is correct.

0 user6101616 over 4 years ago in reply to Subrahmanya

Intellectual 320 points

Ok， thanks,

By the way, is there any other method that can be related to clboutput to pwm1a and pwm1b with gpio145 / 146 instead of clb_setoutputmask? Because our board is ready, we can't change the hard pin connection to GPIO1/GPIO2 temporarily.

Thank you very much!

0 Subrahmanya over 4 years ago in reply to user6101616

TI__Mastermind 24095 points

Hi,

Which part number, package are you using exactly?
I would like to replicate the issue you are observing.
Please share the device details and the try to replicate the issue with the test below
C:\ti\c2000\C2000Ware_2_01_00_00\driverlib\f2837xd\examples\cpu1\clb
clb_ex1_combinatorial_logic
This will help in replicating at my end easily and enable quick closure.

0 user6101616 over 4 years ago in reply to Subrahmanya

Intellectual 320 points

OK, I try to replicate the issue on my board, and show you the result later;

The exact part number and package is as below:

XF28388DZWTS 337pin NFBGA

0 Subrahmanya over 4 years ago in reply to user6101616

TI__Mastermind 24095 points

Thank you. Please update us when you are able to replicate.

0 Subrahmanya over 4 years ago in reply to Subrahmanya

TI__Mastermind 24095 points

Hi, Are you able to replicate the issue? Please let us know if you still have the issue.

0 user6101616 over 4 years ago in reply to Subrahmanya

Intellectual 320 points

Hi,

I have replicated the "Example 1 – Combinatorial Logic" on my board and I can see the complementary PWM waveform from Oscilloscope when the pin route to GPIO 0 and GPIO 1, but I can replicated it when I route to GPIO145 and GPIO146.

So, for the the original question, why can't find the output from GPIO145 and GPIO146 when route to them?

0 user6101616 over 4 years ago in reply to user6101616

Intellectual 320 points

Correct it. It's a waveform with a large duty cycle like this, not a pair of complementary PWM

0 Subrahmanya over 4 years ago in reply to user6101616

TI__Mastermind 24095 points

Hi,

user6101616 said:
Example 1 – Combinatorial Logic" on my board and I can see the complementary PWM waveform from Oscilloscope when the pin route to GPIO 0 and GPIO 1, but I can replicated it when I route to GPIO145 and GPIO146.

So, are you saying that with the example, you could route the output to GPIO145/146. But with your original code you are not able to?

If so, it must be some configuration issue.
I've also cross checked with design team and there is no issue in using GPIO145/146 to route the outputs.

0 user6101616 over 4 years ago in reply to Subrahmanya

Intellectual 320 points

Thank you for your result of double check!

I go on finding out the reason further. Thank you.

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TMS320F28388D: CLB module and ePWM module output association