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Keil: SWDIO no target connected

Francesco Sfragara
Associate
Posted on February 19, 2018 at 14:48

I'm using a stm32f407vg board. Suddenly I can't download my code to flash memory anymore. I'm using the keil toolchain. I tried stm32 st-link utility, but it can't connect to target either. I tried the option 'connect under reset', but it didn't work. I tried to unistall and install again the st link drivers and utility, but it didn't work. 

Can somebody please help me? Thanks.

8 REPLIES 8
Posted on February 19, 2018 at 15:32

Try pulling BOOT0 high, reset, and program/erase via ST-LINK Utilities

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Andrew Neil
Evangelist III
Posted on February 19, 2018 at 15:56

Cross-post: 

http://www.keil.com/forum/63376

 
ACarb
Associate

I've solved the issue following these steps:

-Install STM32 ST-LINK Utility;

-Open it, click on ST-LINK -> Firmware update;

-Plug your board, then click on Device Connect. If the board is recognised proceed with the firmware update (click yes), otherwise check if the drivers are correctly installed;

-Click on Target -> Settings. Under "Mode" select "Connect under reset". Leave all the other settings as default;

-Go on Target -> Connect. You are now connected to the board (see the registers);

-Finally click on the red Rubber figure (Full Chip Erase).

Now you should be able to download your code into the flash using Keil.

Hi, thank you for sharing the solution! I had the same issue and it worked for me too.

ersinkecis
Associate

hi, thank you for all.

but this solution is not working for me. :(

sometimes connecting. sometimes does not connect.

Is there anyone have an idea?

STLinkUSBDriver.dll v5.1.2.0

ST-LINK Firmware v2.J34.S7

Does your device go into a low power mode? Interfere with clocks, or pins related to SWD interface? NRST connected?

Try "Connect Under Reset"

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Up vote any posts that you find helpful, it shows what's working..

like you said, because I use a low-powered power supply. thank you so much.

your solution works!!