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Kinetis - START_FROM_RESET

Question asked by joe hinkle on Sep 9, 2016
Latest reply on Sep 9, 2016 by Mark Butcher

The following comment appears in my startup.s file

 

* STARTUP_FROM_RESET
*
* If defined, the program will startup from power-on/reset. If not defined
* the program will just loop endlessly from power-on/reset.
*
* This definition is not defined by default on this target because the
* debugger is unable to reset this target and maintain control of it over the
* JTAG interface. The advantage of doing this is that it allows the debugger
* to reset the CPU and run programs from a known reset CPU state on each run.
* It also acts as a safety net if you accidently download a program in FLASH
* that crashes and prevents the debugger from taking control over JTAG
* rendering the target unusable over JTAG. The obvious disadvantage of doing
* this is that your application will not startup without the debugger.
*
* We advise that on this target you keep STARTUP_FROM_RESET undefined whilst
* you are developing and only define STARTUP_FROM_RESET when development is
* complete.

 

All my work to date has been having the device connected to a JLink.

 

I now am getting ready to run the device without a JLink connection.  

 

The comment above says that is STARTUP_FROM_RESET is not defined - the cpu goes into an endless loop so that "a debugger" can connect to it.

 

Is this a "general" statement or does it NOT apply to a JLink connected device?

 

Segger has no information that states this "endless loop" debug mode is required for them to get a hold of the cpu.

 

Is the statement for NON-JLink debug devices?

 

Thanks for any clarification.

 

Joe

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