FlexCAN refuses to leave Low Power Mode

norton256 — Thu, 15 Dec 2016 16:52:21 GMT

I have an application where I change clock sources and modes frequently, and the FlexCAN clock source, and baud rates also change to match.

Currently I have FlexCAN enabled in the FBE and PEE modes.

When in FBE, FlexCAN is sourced from the bus clock, which is directly driven by the RTC crystal output and running at a baud of 1.5k.

When in PEE, FlexCAN is sourced from the OSC, which is driven at 10MHz, and CAN is running at a baud of 1M.

In all other MCG modes, the FlexCAN module is either held in freeze or the module is disabled.

I am currently running into a situation where during one of these clock changes, the FlexCAN never comes out of module disable (or low power) mode.

The sequence is as follows:

PEE mode, FlexCAN operating.

FlexCAN enter freeze

Switch to FEE mode.

FlexCAN disabled.

Switch to FBE mode.

FlexCAN clock source changed, and module enabled <------ here the LPMACK bit never goes low

I am using the MK60FN1M0VMD12.

Thanks!

Re: FlexCAN refuses to leave Low Power Mode

Kan_Li — Thu, 22 Dec 2016 03:40:23 GMT

Hi Nick Borton,

I have tried the same process on TWR-K60F120M, but looks like the LPMACK bit went low on my case, I used PE to generate the driver code, so maybe it was a code issue? Please kindly refer to the following for details.

I also attached my test code based on KDS 3.0. Please kindly refer to it for more details.

Hope that helps,
Have a great day,
Kan

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topic FlexCAN refuses to leave Low Power Mode in Kinetis Microcontrollers

FlexCAN refuses to leave Low Power Mode

Re: FlexCAN refuses to leave Low Power Mode