L475E is not recognized by my PC using STLINK [SOLVED]

[SSeij.1]

Hello

I have recently acquired a B-L475E-IOT01A2 IoT node, which has an integrated SMT32L475VGT6 MCU microprocessor.

I have installed the STLINK V2 driver and tried to connect to it via a microUSB type B cable to the USB_STLINK port (CN7), with jumper JP4 on pins 1 and 2.

So LED5 lights green and I proceed to load (in CubeIDE) a project previously generated with CubeMX. Then I receive the following error message: "No ST-LINK detected! Please connect ST-LINK and restart the debug session".

Therefore, I try to connect through CubeProgrammer to the micro-controller but I am not able to. I have tried to update the STLINK driver firmware and I still can't connect.

I have also downloaded and installed OpenOCD as an alternative.

I have repeated the process on both Linux and Windows (because I have read in other forums that many users have had problems with the STLINK driver on Linux).

So I've been at a loss and unable to transfer a project for a while now.

I suspect it may be a bootloader thing, as my understanding is that the bootloader stucks into the RAM and needs to be accessed in USB DFU mode in order to flash the device.

However, for this I would think that at least my device should first be recognized by my PC, and this is not the case. any suggestions as to what I should check?

--

On the other hand, I have been consulting the electrical schematics and noticed a detail, which despite my bewilderment, is perhaps related to my problem.

First of all, a USB-A connector has four wires, and a microUSB-B connector has five. Pin number 4 is not connected.

According to the documentation of my L475E, the fourth pin of the CN7 connector is used for USB_STLK_ID, whose signal will be mixed and filtered together with the differential pair (the data) in U18, to finally be delivered to the STLINK MCU itself.

 

Maybe my PC does not recognize my micro-controller just because of the absence of this wire on my USB cable? Is it necessary with this IoT node model to buy an interface?

Thank you very much

[MM..1 · Accepted solution]

Your issue is bad cable or PC USB. Dont mix STLink and DFU.

Use profesional micro USB cable.

[SSeij.1]

Yes, I didn't expect it to be the bad cable. I tried using another one and now it works. I feel stupid :(

Anyway, thanks.