ST_LINK V2 Not detecting Target

[Pas Kol]

Posted on December 26, 2017 at 20:23

So I made a custom STM32F446RET6 board and I first used a mini ST_LINK programmer to connect to the MCU. I was able to program it but couldn�t debug it since the mini ST_LINK programmer doesn't have the SWO pin. I used STM32 ST-LINK Utility and Keil to program the chip.

I then purchased the ST_LINK V2 programmer from ST but it doesn�t connect to the MCU (target). My laptop does recognise the ST_LINK V2 programmer since I have the stsw-LINK009 software installed. The SWCLK. SWDIO, and SWO pins are directly connected to the male headers as seen in the pictures.

Here are the Connections:

I also attached the trace.log file from STM32 Utility: 

Any ideas as to why this is happening?

#stm32f4 #debugging #no-target-connected #keil-ide #st_link

[Kenta Chang]

Posted on December 29, 2017 at 06:11

Hello, 

I am a new user for STM32F446, and I made a board to learn the STM32F446 this week. But have a problem: Fatal error, ST-LINK V2, No MCU device found. Session aborted!

Could you please help me to solve this issue?

[Kenta Chang]

Posted on December 29, 2017 at 11:03

Hi, 

I find the connection was Not correct on ST-LINK V2 side.

[Andrew Neil]

Posted on December 29, 2017 at 14:49

Note that what you show there is not an 'official' ST product - it is a cheap chinese knock-off.

I have noticed with these that the target connector pinout can differ from one item to another - so check the markings on the case carefully ...

[Tesla DeLorean]

Posted on December 29, 2017 at 17:27

Review the schematic, the error suggests the chip isn't running, or is wired up wrong.

Check voltage observed on NRST and VCAP pins.

[Kenta Chang]

Posted on December 30, 2017 at 15:29

Thanks.

The voltage on NRST pin is 3.27V, on VCAP1 pin is 1.12V and on VCAP2 pin is 0.20V. 

By the way, could you please let me know: what voltage are correct on VCAP1 and VCAP2 ?

[Tesla DeLorean]

Posted on December 30, 2017 at 15:35

1.25V

Make sure the chip has the correct orientation.

[Kenta Chang]

Posted on December 30, 2017 at 18:05

Thanks.

According to STM32F446 datasheet, 

as Regulator On, the voltage on VCAP pin is 1.25V,

as Regulator Off,  must supply 1.25V to VCAP pin.

Can I setting Regulator Off by pull-up or pull-down resistor? How to do?

[Tesla DeLorean]

Posted on December 30, 2017 at 18:42

Not sure you have regulator control on a 64-pin device.

You should perhaps compare your design with that of the NUCLEO board, making sure all the supply pins are wired up correctly and the pin numbers are all in order.

The secondary signs-of-life check would be to use USART1 (PA9/PA10) in the System Loader mode (BOOT0=High), use 9600 8E1 and send an 0x7F byte, and check for 0x79 response.

Not looking to debug the design in this manner.

[T J]

Posted on December 30, 2017 at 21:54

I am using the '767 -208

I used a 2.2uF low ESR cap on both of those two Vcap pins.

they are both sitting at 1.31v