Linux/AM5728: McSPI issues

xixi

Expert 2990 points

Part Number: AM5728

Tool/software: Linux

Hi all:

We have an DAC board which is am5728 + DAC chip.

The hardware diagram is like bwlow:

The am5728 output the digital signal to the DAC chip.

And then the DAC chip transferd to analog signal.

We use spi_test application to test this DAC board.

Now we found an issue!!!

The Analog signal is not continuous.

For example we output an sine wave, and the DAC can measured the sine wave

but sometimes the DAC chip won't output any signal in a certain 10 milliseconds.

the phenomenon will definitely appear, but it doesn't happen often.

So we doubt whether the process is scheduled in the 10 milliseconds.

But we don't know how to solve this issue, anyone can help us.

Thanks

regards

over 6 years ago

0 Krunal Bhargav34 over 6 years ago

TI__Mastermind 45015 points

Hello,

I am wondering if the signal coming out of AM5728 is delayed by 10 ms or the signal coming out of the DAC is delayed by 10 ms.

Regards,
Krunal

0 xixi over 6 years ago in reply to Krunal Bhargav34

Expert 2990 points

Hi Krunal

Thanks for your reply.

The below picture is my test signal.

the yellow signal is analog signal, the blue signal is mcspi clk

From the test signal,in the 10ms, the mcspi output nothing.

so we doubt whether the process is scheduled in the 10 milliseconds?

Regards

xixi

0 xixi over 6 years ago in reply to xixi

Expert 2990 points

HI all:

The issue is very critical for us, Anyone else can help us.

Thanks

regards

xixi

0 Krunal Bhargav34 over 6 years ago in reply to xixi

TI__Mastermind 45015 points

Hello,

I am wondering if you could please verify your SPI configuration using SPIdev . Here are a few example references:

https://e2e.ti.com/support/processors/f/791/t/515698

https://e2e.ti.com/support/processors/f/791/t/631995#pi320966=3

https://e2e.ti.com/support/processors/f/791/p/507226/1840389#1840389

Regards,
Krunal

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Linux/AM5728: McSPI issues