stm32f405rgt is not detected after connecting with st link not even show on device manger

[Rizvi]

Don't know weather my Stm32F405 (new) needs a bootload or not? 

I have designed a custom stm32 board in order to detect my stm32 by the computer for the code uploading i connected my stm32 externally with a TQFP breakout board with my ST-LINK V2 , all the necessary connections have been made after that when i try to connect it on stmcubeide i shows can not connect i tried it with stm32 utulity software as well same result arise. 

when powering my stm using st link or external power all the vdd pins are getting 3.29v while the vcap is 1.2v and 1.6v (2.2 uf capacitors) . 

i just want to make sure that i am doing correct wiring or not and if yes then what is the bootload issue? is that need to do the bootloading externally 

in this picture ignore all the connection except power and swclk and swdio connection...

thankyou in advance 

 

 ? 

[Peter BENSCH]

Welcome @Rizvi, to the community!

BOOT0 needs to be connected to GND, directly or via a resistor of 10k.

VBAT needs to be connected to VDDA if you don't have a battery or other storage.

Regards
/Peter

[Rizvi]

i did connect boot0 by gnd directly and vbat connect to vdda that also connect with vdd, but it still it didnt found its target on st link utility ? by j

[Peter BENSCH]

How does the ST-LINK/V2 looks like you've connected to this board?

Can you upload a photo?

[Rizvi]

the actual circuit is a bit messy because of a number of testing but let me show you and explain it:

    STM 32                                                     ST LINK V2

 pin 55(SWO)  connected via 22ohm --->    SWO pin 13

pin 7 (NRST) connected via 22ohm + 0.1uf -----> PIN 15 (RESET)

Pin 49 (SWCLK) via  22ohm                  ----->  pin 9 (SWCLK)

Pin 46 (swdio) via  22ohm                  ----->  pin 7 (SWDIO)

VDD+VDDA+VBAT (3.3V) ----->  pin 1 (VCC)

 

GND ----->  pin 1 (GND)

pin 60 (BOOT0) connected to ground directly

VDD CONNECTED VIA 0.1uF AND 4.7uF AT ONE VDD 

VCAP CONNECTD WITH 2.2uF 

unfortunately there is a voltage drop at the vcc of the stm32 i guess something with my vcc connection is wrong.

 

[Rizvi]

This is the real messy circuit i have made for testing purpose ignore the vero part its nothing but just a 33v regulator converting 5v to 3.3v 

[Tesla DeLorean]

So you can see the ST-LINK in Device Manager now?

You need Target VCC connected to the ST-LINK/V2 to power the IO buffers. Would suggest VCC GND SWDIO SWCLK NRST

You should double check your supplies and grounding. Both VCAP pins should be the same, around 1.2 or 1.25V

[Rizvi]

Yes i can see the st-Link v2 in my device manager and although i have connected the vcc of the st link to my vcc of the stm32 pins and other connection like you said as well i have checked by giving external supply also its showing 3.3v at each vcc pin but when i connect the circuit using st link to my computer on stm cubeprogrammer this stuff is making me triggered why that voltage is less? here is my circuitry schematic between st link and stm32

 

[Peter BENSCH]

Firstly, you should update the rather old firmware on the ST-LINK/V2, which you can do directly via the STM32CubeProg.

Then the CubeProg will show a lower voltage because it measures - or thinks it measures - this voltage on its VDD pin from the target. Assuming you have connected VDD and GND correctly (and therefore only read to the end), your ST-LINK could also be damaged. For this reason, it would be very useful to connect a KGB (Known Good Board, e.g. a NUCLEO) to check the ST-LINK/V2 for function.

But I am sure that you have connected your ST-LINK incorrectly: you think you have connected the blue wire on your photo to pin 1 of the 20-pin connector of the ST-LINK, right? In fact, it is pin 19, as you can see in fig 10 of UM1075. Please check this again and connect the wires correctly.

Regards
/Peter

[Rizvi]

As you said and manual too pin 19 is vcc but i have checked my st link pin by multimeter it shows no voltage (in milli) in my st link v2 only one pin is giving 3.3v which is the pin 1 of stlink ? is it possible not my connection but my st link is not working properly?

[Peter BENSCH]

Well, if you cannot measure the internal 3.3V of the ST-LINK at pin 19, which is normally found there, you have probably damaged something in the ST-LINK. Theoretically, however, the ST-LINK could still function despite the lack of voltage on pin 19, as there should be an internal resistor that may have burnt out. That's why I wrote to check the ST-LINK on a KGB.