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Visitor II
July 31, 2019
Question

Му Core is held in reset!

  • July 31, 2019
  • 3 replies
  • 789 views

Hi All,

My board is built on the STM32F746IG.

Some time after the launch of the firmware (3 different firmware) access via SWD is unavailable.

Stm32_Link_Utility reports:

- Core is held in reset

- Can not connect to target!

.....

.....

Vnrst = 0.3 V, despite the connection to Vcc through resistor.

When I select the "Hot plug" mode, I can connect, but the flash is not available and cannot be erased.

This goes on for a long time.

I turn off the power. I measure the resistance of the line nrst.

Sometimes I just wait a long time :)

The board is again available, within an hour or two:

Vnrst = 2.98 V

The firmware works.

After some time, the problem repeats.

    This topic has been closed for replies.

    3 replies

    Graduate II
    July 31, 2019

    You have VDDA connected?

    Capacitors on VCAP pins? Voltage measured there?

    ANapaAuthor
    Visitor II
    July 31, 2019

    0690X000009ZfJlQAK.pngVCAP1 - 3.3V

    VCAP2 - 1.16V

    VDDA - 3.3V

    ANapaAuthor
    Visitor II
    July 31, 2019

    Correction0690X000009ZfLSQA0.png