How can I detect if a debugger is attached to a Kinetis via SWD_CLK and SWD_DIO?

[markminich]

I want to determine at runtime if a debugger is attached, and disable/enable printf()'s based on that. (Yes, I understand that this alters the timing of things and thus an application's behavior.) How can I tell if a debugger is attached to the Kinetis's SWD_CLK or SWD_DIO pins? Though I'd expect it to not matter as far as the solution goes, I'm using P&E Multilink. My part is a MKL26Z128VFM4 (KL26 sub-family).

[ZhangJennie]

Hello Mark,

in debug mode,  we can detect clock on SWD_CLK pin. while in run mode there is not.

so one idea is to use a free GPIO connect SWD_CLK, set this GPIO as input. use this GPIO detect if SWD_CLK has clock. if yes, it's debug mode. otherwise, it's run mode.

Have a great day,
Zhang Jun

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