No traceswo output on stm32H7xx

[Florian Otte]

Posted on March 16, 2018 at 07:40

Hi Forum. I am new to the H7 line of processors and the first thing I tried is getting printf() output on the traceswo pin of my nucleo-H743ZI. What I have tried:

1. The 'Everything out of the box' way:

Use cubeMX to configure sys to async trace, configure clocks, enable master clock out (to verify clock speed with a logic analyser).

Import the project to atollic truestudio and configure debugging to use the SWV, with the specific baudrate and core clock.

Write simples mainloop:

while(1) {

    ITM_Sendchar('T');

    delay(xxx);

}

Start a debugging session, configure trace port 0 and start tracing -> no output in atollic truestudio, no output on PB3 (verified with logic analyser)

2. The 'Do some manual work and hope the rest will resolve' way:

Same as above, with the exception of enabling the ITM unit manually:

CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;

CoreDebug->DEMCR |= CoreDebug_DEMCR_VC_CORERESET_Msk;

ITM->LAR = 0xC5ACCE55; // Unlock Lock Access Registers

ITM->TCR |= ITM_TCR_DWTENA_Msk;ITM->TCR |= ITM_TCR_SYNCENA_Msk;ITM->TER |= 0x01; // Port 0ITM->TCR |= ITM_TCR_ITMENA_Msk;

Start debug session, enable tracing in atollic studio, THEN call my own init function - since the debugger overwrites the register values -> No traceswo output

3. The 'Do another variation of the non-working example' way:

Same as above, but I let the debugger handle the initialization and have the processor my init code before tracing is enabled through atollic stuido

-> Same result

4. The 'Try to do it by the book' way:

Here I really failed. What I tried:

Configure ITM manually, configure the SWO and SWTF unit manually.

Here my problem is that I do not know where SWO and SWTF are found in memory. The reference manual tells me that I can look up these adresses through the System ROM tables at adress 0xE00E0000.

However acessing these yields a fault -- Have not implemented the different faults, so i can not tell which is the one thats biting my ***! So I thought: Maybe I need to access these in priviledged mode.. same error.

(Atollic truestudio version - if that matters):

Atollic TrueSTUDIO� for STM32, Built on Eclipse Neon.1a.

Version: 9.0.0

Build id: 20180117-1023

Has someone a working example for trace output on the traceswo line on the nucleo-h743zi using atollic truestudio?

Any help or suggestions are apprechiated!

Florian

Addendum:

I received a response from Atollic.

XXXXX XXXXXXX

(Atollic Support)

Mar 16, 09:17 CET

Dear Florian,

There is a known problem with the STM32H7 which we have a ticket for at the moment. We hope to have this fixed until the next release. However, we haven't had a response from the correct ST department just yet if there's a problem with the MCU itself or if we've made a faulty configuration in the software somewhere. We're going to try to reach out again for a response.

Best regards

XXXXXX, Atollic Support Team#atollic-truestudio #itm-swo-trace #nucleo-h743zi

[Tesla DeLorean]

Posted on May 18, 2018 at 23:27

Like this?

[Tomas DRESLER]

Posted on May 21, 2018 at 13:50

Exactly.

[Tesla DeLorean]

Posted on May 21, 2018 at 14:25

Ok, that didn't seem viable of the STM32H743I-EVAL, didn't see any solder-bridge/jumpers there, will try on NUCLEO-H743ZI later.

[Florian Otte]

Posted on June 19, 2018 at 08:25

Short Bump + a short reminder, that theese issues are not solved.

Looking at you ST. It has been over three months now. The errata sheet from May,2018 does not include a note, or any advisory and the datasheet has not updated since November,2017.

That's very discouraging. Is someone working on it?

[Tesla DeLorean]

Posted on June 19, 2018 at 08:31

Well a mob is starting to assemble

https://community.st.com/0D50X00009XkhURSAZ

[Tesla DeLorean]

Posted on June 21, 2018 at 18:38

https://community.st.com/0D50X00009nNBBHSA4

 

[FDixo]

Anyone managed to get link above working (or below if you are upside down)?

[Tesla DeLorean]

It didn't survive the jump to the new forum, currently still exists here

https://st-microelectronics.jiveon.com/docs/DOC-2098-how-to-use-the-swo-on-stm32h7-devices

I condensed it down to this

void SWD_Init(void)
{
  *(__IO uint32_t*)(0x5C001004) |= 0x00700000; // DBGMCU_CR D3DBGCKEN D1DBGCKEN TRACECLKEN
 
  //UNLOCK FUNNEL
  *(__IO uint32_t*)(0x5C004FB0) = 0xC5ACCE55; // SWTF_LAR
  *(__IO uint32_t*)(0x5C003FB0) = 0xC5ACCE55; // SWO_LAR
 
  //SWO current output divisor register
  //This divisor value (0x000000C7) corresponds to 400Mhz
  //To change it, you can use the following rule
  // value = (CPU Freq/sw speed )-1
   *(__IO uint32_t*)(0x5C003010) = ((SystemCoreClock / 2000000) - 1); // SWO_CODR
 
  //SWO selected pin protocol register
   *(__IO uint32_t*)(0x5C0030F0) = 0x00000002; // SWO_SPPR
 
  //Enable ITM input of SWO trace funnel
   *(__IO uint32_t*)(0x5C004000) |= 0x00000001; // SWFT_CTRL
 
  //RCC_AHB4ENR enable GPIOB clock
   *(__IO uint32_t*)(0x580244E0) |= 0x00000002;
 
  // Configure GPIOB pin 3 as AF
   *(__IO uint32_t*)(0x58020400) = (*(__IO uint32_t*)(0x58020400) & 0xffffff3f) | 0x00000080;
 
  // Configure GPIOB pin 3 Speed
   *(__IO uint32_t*)(0x58020408) |= 0x00000080;
 
  // Force AF0 for GPIOB pin 3
   *(__IO uint32_t*)(0x58020420) &= 0xFFFF0FFF;
}

[Tesla DeLorean]

We might have to revisit this on the ST-LINK V3SET and Keil, the V3 is using a 15 MHz SWV clock, not 2 MHz, so the math changes. This was on a 120 MHz L4+ board, so the frequency/multiples might be different in other environments or use cases.