Is it possible to view registers of a running target inside STM32Cube?

[GHrib.1]

I would like to view/modify values of registers while in debugging perspective, while the target is in running state. So far I have discovered that you can view registers only during pause(resume) of program in the SFRs window. Is it possible to have some type of continous refresh of registers values?

[MM..1]

Maybe yes in live expression, and change in pause over bit access

[S.Ma]

Yes live watch or live expression is one way. While the code runs, the debug interface is used to make a memory read access stealing a bus cycle, like a dma would. Of course it is not real time. Something I didn't use was watchpoint, it is like breakpoint on data value matching. If supported, can give other ways to debug a code.

[GHrib.1]

How can I view register in Live Expressions window?

Lets say I have a simple blink program, the values inside GPIOA_ODR register should change. How can I see this change?

If I write GPIOA_ODR inside Live Expressions I get Failed to Evaluate Expression inside value space.

[Tesla DeLorean]

Which registers? The MCU's ?

With peripheral registers it gets to be a bit invasive. The stuff in general can change millions of times a second..

What exactly are you trying to achieve? Perhaps there's a better way or approach?

[GHrib.1]

The more the better, but i would be satisfied with peripheral registers (TIM, DMA, ADC).

That is true, but when I worked with Texas Instruments CCS I found it very useful, even though it is not real time. I found it very useful for debugging strange behavior of peripherals, where registers are your only source of information.

I don't have a specific problem yet, I am only preparing for them.

Lets say that I have simple blink program, GPIOA_ODR register should therefore change its value. How can I see this change in registers value during debugging?

[Semer CHERNI]

Hello @Gašper Hribar​ 

First let me thank you for posting.

To watch the IP register, the STM32CubeIDE provide a specific view for this purpose called SFRs:

 

I hope this answer solve your question. If yes, please mark the answer as a Best Answer.

Semer.

[GHrib.1]

I am familiar with SFR window. The problem I have is the fact, that this view doesn't show changing of registers values during runtime (values update only on "pause").

[Rim LANDOLSI]

Hello GHrib.1,

For live update you can use live expressions view.

CubeIDE 1.11.0 to be released soon will include live update from the SFR view .

[GHrib.1]

How can I use live expressions view to look into registers?

Lets say I have a simple blink program, the values inside GPIOA_ODR register should change. How can I see this change?

If I write GPIOA_ODR inside Live Expressions I get Failed to Evaluate Expression inside value space.

I am very happy to hear about it :D . It would also be great if the opened registers inside SFR view would stay opened after changing perspective (DEBUG->EDIT->DEBUG). Currently I have to open registers I am interested in every time I go into DEBUG perspective.

[MM..1]

In your code create u16 variable and insert SFR for monitor to it in some refresh code place. For example systick int .

_IO uint16_t mon_odr;
 
mon_odr= GPIOx->ODR;

[Jot.eS]

You must use the memory address of the register.

E.g. if the address of GPIO_ODR is 0x40020014, then you have to write *0x40020014 in the live expression window. Please note the asterisk in front of the address.

[GHrib.1]

Thank you, I got some response, but it isn't best for readability. Live expression view presumes that this pointer is pointing to an integer, which is correct (register is 32-bit). If you want to see the values of register bit by bit, you have to convert int to binary. My question is if i can somehow tell the Live expression that i would like to see only one bit?