RTOS/CC1310: Drastic changes in temperature cause chip frequency calibration to fail

user4959119

Part Number: CC1310

Tool/software: TI-RTOS

Hi，Team

During the high and low temperature test, I encountered a problem that the chip communication failed for a while, but it was solved by using the cmd_Fs command in the main loop. Technical support tells me that it is due to the temperature change, I wonder if the frequency calibration failure will cause the timer to count incorrectly? Or some other crystal-related problems?

Thank you！

over 6 years ago

0 Christin Lee over 6 years ago

TI__Guru 56345 points

Hi,

What do you mean by the timer to count incorrectly?

Can you post your code snippet?

0 user4959119 over 6 years ago in reply to Christin Lee

Expert 2215 points

Hi，Christin Lee
I mean that the frequency synthesizer will perform a calibration before the RF transceiver. If the temperature causes the calibration to fail, does the timer also lose its accuracy ?For example, a function like Tasksleep (1000) will fail.

0 Christin Lee over 6 years ago in reply to user4959119

TI__Guru 56345 points

The temperature does not cause the calibration to fail.
Once the calibration is done, if you change the temperature without recalibrating, then your radio communicate will not work. The reason that the radio communicate failed, it's because of crystal frequency drift away.(You are not sending and receiving on the same channel anymore).
Frequency change will certain affect timer but it won't make tasksleep to fail, but of course the timer value will drift.

In your previous post, the answer is "
In proprietary mode, re-calibration the freq. synth will be automatically triggered when switch between TX/RX. But in your test, the sender will never switch to RX, and the receiver will never switch to TX, so the re-calibration will not be triggered."

0 user4959119 over 6 years ago in reply to Christin Lee

Expert 2215 points

This is my previous post：e2e.ti.com/.../2804966

My sender switches to receive mode with RF_cmdPropTx.pNextOp after sending the data, and sets the timeout time to 500ms. At the same time, my receiver sends the data with RF_cmdPropTx command after receiving the data.

So I think that I can switch between sending and receiving every time. Now I really don't understand the real reason for this problem. It seems that everything is very satisfactory, and it is normal, even if the crystal is our official recommendation.

I hope your answer.

0 Christin Lee over 6 years ago in reply to user4959119

TI__Guru 56345 points

What's the problem you are having now?
Are you not able to use task_sleep function? Or are you not able to receive packets?

0 user4959119 over 6 years ago in reply to Christin Lee

Expert 2215 points

I have no problem now, and the problem has been solved. What I want to know is the real cause of the problem?

0 Christin Lee over 6 years ago in reply to user4959119

TI__Guru 56345 points

How did you solve it? I am not seeing a full picture of what your problem was and what fix you have applied.

0 Christin Lee over 6 years ago in reply to Christin Lee

TI__Guru 56345 points

Close thread due to inactivity.

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RTOS/CC1310: Drastic changes in temperature cause chip frequency calibration to fail