Clock Failure on Relax Kit

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Hi,

I was working on the relax kit and noticed that the PWM output frequency is not the exact same as I had configured in the App. When I set 100KHz, I get 20KHz only. I checked the crystal clock frequency supplied to the uC and found no signal. I assume there has been a clock failure and it must be using the internal clock. I went through the datasheet and found that the internal clock has a frequency of 24MHz (calibrated). How can I modify the App such that it uses this internal clock and help me give exact frequency as I set in the PWM App?

Thank You.

Regards,
ashare
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5 Replies
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Update:

It seems the crystal oscillator is not the problem. I replaced it and checked. Problem sustains. Can somebody suggest a possible solution? Thank You.

Regards,
ashare
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Hi ashare,

There is clock selection on the CLK001 app.
From there, you can choose the system clock to Backup Clock Source where it will use the 24MHz fast internal clock.
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Travis
Employee
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First solution authored Welcome! 500 replies posted
Hi ashare,
Give this example a try which is able to generate 100Khz PWM at P3.0 of your XMC4500 relax kit. If this is not working good, then you can be sure that something is not right with your hardware.
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Hi Jackson/Travis,

Thanks for your replies. I had tried to switch to the internal clock, however the output frequency still continues to be divided by 1/5th to what I set in the PWM App. So here is what I did, I imported the project Travis gave me into Dave and flashed it to my Relax kit. Observed the O/P on Port 3.0, the problem persists. I am getting 20KHz frequency. In this regard, may I ask you how sensitive is the Relax kit to ESD. I am curious to know because I haven't used any ESD straps while handling the board just like other boards like the Arduino. Could it be an issue caused due to ESD?

Regards,
ashare
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Travis
Employee
Employee
First solution authored Welcome! 500 replies posted
ashare wrote:
Hi Jackson/Travis,

Thanks for your replies. I had tried to switch to the internal clock, however the output frequency still continues to be divided by 1/5th to what I set in the PWM App. So here is what I did, I imported the project Travis gave me into Dave and flashed it to my Relax kit. Observed the O/P on Port 3.0, the problem persists. I am getting 20KHz frequency. In this regard, may I ask you how sensitive is the Relax kit to ESD. I am curious to know because I haven't used any ESD straps while handling the board just like other boards like the Arduino. Could it be an issue caused due to ESD?

Regards,
ashare


If you are not able to get 100KHz PWM from the provided example which means the board might be spoiled. Do you have the opportunity to change to another spare XMC4500 relax kit, please contact your sales for an exchange or a spare to verify this problem.
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