ETM trace with Ulink pro in STM32CUBEMX

[William chang]

Posted on March 03, 2018 at 16:10

I am using STM3210C EVAL board (stm32f107vc). UlinkPro debugger.

Here is the tutorial I found from keil.com. 

http://www.keil.com/support/man/docs/ulinkpro/ulinkpro_stm32f10xxx_etm.htm

 

Here is the snipping.

So, when we need to using ETM trace, we just need to enable the Trace PORTs clock, and configure them as AFIO with highest speed, then set the DBGMCU_CR, that's it?

What I found in the STM32F107 user manual is this!

it looks different!

As I config in the CUBEMX with trace sw (4 bits), the output code doesn't do any thing related to the trace PORTs.

If I don't use trace.ini (as KEIL says) to pre-configure the MCU, ETM also works!

What rules should I follow when ETM tracing STM32 MCU? 

Boys.Bob

‌ Please pay your attention? thanks ^ ^

#etm

[Bob Boys]

Posted on March 03, 2018 at 20:39

Hello

I did not write the instructions on keil.com - but they look accurate.

1)  The code you display for the .ini file is to set the Trace Port GPIO pins to handle ETM the best.

2) The code you show from the ST manual is something different - this configures ETM inside the CoreSight module in the STM32.

3) uVision sets this ''under the hood'' when you enter Debug mode.  You do not need to set these manually.

Why does the ETM trace work even without the .ini file ?  There are several possibilities:  the major one that these are set somewhere else.

1) Is CubeMX configuring these in your code somewhere ?

2) In the latest Software Pack - there is a new entry - in the Target Driver Setup window there is sometimes a new tab:  Pack.  See below.  This can contain a file dbgconf as shown below.  This is used instead of the .ini file in the older way.

3)  It doesn't need to have the GPIO pins configured ?  This might mean ETM won't work reliably at the highest speeds.  It all depends on what needs to be turned on or off - some parts need a Alternative Pin to be switched to ETM.

You can check these by examining the GPIOE registers to see what is set in there.

Note:  in the .ini file - if you RESET the processor with uVision - you would lose the effect of this ini file.  Adding this code will rerun the ini file after a RESET without exiting and re-entering Debug mode:

// Executed after reset via uVision's 'Reset'-button

FUNC void OnResetExec (void) {

  SetupTrace();

}

What's New:  With MDK 5.25, you can now display Exceptions in graphical format in Event Viewer and System Viewer even if you are not using an RTOS.  Code Coverage and Performance Analysis still works and Trace Triggers were added a while ago.

Hope this explains what is going on in your system.

Thanlks

Bob Boys

[William chang]

Posted on March 04, 2018 at 04:11

In the pack. I found this.

In my case, I will leave all unchecked.

Then I look in the Text Editor.

DbgMCU_CR = 0x00000000; !!!

What is the pack doing?!!!

Maybe I can see the register

who will run first

.

But this really get people confusing.

if 

*

.dbgconf first, the finally 

DbgMCU_CR  will be rewrite to 0x000000E0. That is ok. 

But if my *.ini file (Project - options - debug ) run first, DbgMCU_CR  = 0; 

there are 2 ways for us to configure the ETM tracing ?

1. add *.ini file in the Project - options - debug and write the code by myself, disable the pack?

2. Just use *.

dbgconf

 only, but I still have to add some code in the file ? ( the pack debug initialization file just imperfect now, It may be updated later?)

[Bob Boys]

Posted on March 04, 2018 at 08:18

Hello

It looks like the pack file doesn't have ETM enabled.  This could be an early version and someone expected an .ini file to be also used.  I will point this out and get it fixed.

There are three ways to enable ETM that I know of::

1) a .ini file.  This was the first way we did this - before packs were available.  We did not take this away when the newer method came to preserve some compatibility.  We now can use this to configure the new ULINKplus and other things.

2) the dbgconf file located in the Pack. This can be disabled.

3) Since CoreSight information is public - you can enable it in your source code as you saw in the ST document.

I suppose you can set a Watchpoint to the address of

DbgMCU_CR

and the user program will stop when this is written to exposing the instruction doing this - or at least very close.

It sounds like you have ETM working quite well.

Thanks !

Bob