Logic analyser shows difference between genuine (not communicating) and cheap (communicating)ST-Link

[SSmit.13]

Hi

  I am having issues with programming a target board with a genuine ST-Link board (got from Farnell) . I have been using a cheap programmer that works, and as I have upgraded to the new IDE (from atollic) it fails to work , but still works on the STM32CubeProgrammer. The genuine ST-Link communicates with the PC, but cant connect to the Cube Programmer, while the cheap one works perfect. I have set the ST-Link Configuration to the below.I also have the images from the logic analyser during a connect sequence. As this is on the same target board and the cheap one work, I think this points to an issue with the genuine programmer. I managed to get a loan of another genuine one, and that too has the same effect. A noticeable difference the serial clock starts before the Reset line goes low , unlike the genuine no clock  till a good while after the reset line , and I assume it times out before this. Anyone any idea, I am totally baffled. I checked all the voltages on the board and are correct. The cheap one works on software reset as well as hardware.

Any help would be great

Scott

 

[Pavel A.]

Get a new USB cable. Very best quality you can find.

[Tesla DeLorean]

Detect the board or the MCU? Obviously I hope this would all work, but perhaps start looking at different computers, cables, drivers, OS, etc. Avoid hubs and docking stations. DELL's have historically been a bit quirky, but they may skew the statistics due to the volume of the products in the market place.

Likely to find 4 MHz is TOO FAST for the CM0(+) cores to hack. ST's defaults can be too aggressive at times, and their fall-back and recovery game is also poor.

Might I suggest providing the analyzer plots at the same scale? Perhaps review the signal in the context of what's generated by the ST-LINK, and the expected/anticipated responses from the core, and square the circle from that perspective.

[SSmit.13]

I tried a few cables, and as it is a new programmer, I also used the cable that comes with it. I assume this is good enough

[SSmit.13]

The STM32CubeProgrammer detects the programmer on the genuine, but not the MCU. As mentioned it works with the cheap and the Nucleo Board I have (used the ST-LINK only to my board).

I have tried another computer, a new one we have with no ST software on it, and still the same. I tried all the speeds .

I couldnt display the genuine analyser output as it takes too long for the sck to start. Both are sampled at 10MHz , and noticed the genuine skl line is low , compared to high in the cheap model

[Pavel A.]

@Amel NASRI @Peter BENSCH  ?

[TDK]

Yet another thread for same issue:

https://community.st.com/t5/stm32cubeide-mcu/autostart-local-gdb-server-not-working/td-p/579170

Feels like a firewall issue.