ST-Link connect ok for Nucleo_G474RE, but NOT for Nucleo_G491RE

[flyer31]

Hi,

I really have much exprience with many STM32 products (STM32H7, STM32F4, STM32L, STM32G0, STM32G4).

Typically for first board check of new PCB I use ST-Link.

I have a weird problem, that my ST-LINK refuses to connect to STM32G491 devices (neither on my own PCBs, nor for Nucleo-G491).

If I resolder the controller to STM32G473, then connect works fine. Also Nucleo-G474 connect works fine in ST-Link.

Is there anything special to do to connect to STM32G491? (Nucleo-G491 ... I have two such boards, both refuse to connect, but LED blinking all fine... same as G474).

[Diane POMABIA]

Hi @flyer31​ ,

Which STLINK do you use?

Diane P

[flyer31]

I just downloaded newest ST-LINK from STM32 Nucleo-G491 page:

Menu ST-LINK - Help - About - Info:

STM32 ST-LINK Utility v4.6.0.0

STLINKUSBDriver.dll v5.1.2.0

ST-LINK_CLI.exe v3.6.0.0

The Firmware of the Nucleo_G491RE is shown (Menu ST-LINK - ST-LINK - Firmware Update - Device Connect ... here strangely Device connect works, but only in this "Firmware update window" (also if I plug the Nucleo_G491RE to my Win10 PC by USB, the USB window pops up...)):

The "Firmware update" shows after "Firmware Device Connect" for "Current Firmware": V3.J10.M3

The "Firmware update" for my Nucleo_G474RE (which works nicely for "normal" Device connect) shows for "Current Firmware": V3.J2.M1

[flyer31]

One strange difference in the "Firmware update window":

The working Nucleo_G474RE shows in the MCO output line: "Default (HSI/2 8MHz)" marked.

The non-working Nucleo_G491RE shows in the MCO output line: "Other" marked. (this checkbox "Other" appears only for Nucleo_G491RE ... the Nucleo_G474RE does not even show such checkbox "Other").

My second non-working Nucleo_G491RE shows "Current Firmware" V3.J6.M2, and also "Default (HSI/2 8MHz" marked (also does NOT show "Other").

Both Nucleo_G491RE do not connect by toobar button / Target menu (but they strangely connect in the "Current Firmeware" menu).

[Mike_ST]

Hello,

ST-LINK UTILITY does not support G491.

Please try to use STM32CubeProgrammer.

https://www.st.com/en/development-tools/stm32cubeprog.html

[flyer31]

Ups, this is surprise to me.

So there is a real severe difference between STM32G474 SW-Debug-Interface and STM32G491 SW-Debug-Interface? (I always use the two wire debug lines SWDIO and SWDCLK together with NRST-Line, so together with GND it is a small 4 pin connector).

Is it possible to use Keil uVision Debugger with STM32G491 (SWDIO/SWDCLK), or should I expect here similar problems as with ST-LINK? (As Interface to Keil uVision, I use such a Nucleo ST-LINK interface...).

[flyer31]

What a surprise, you are right ... CubeProgrammer works nicely, and also Keil uVision.

Thanks a lot, this made my day... .

(But it's a BIT nerving, that there seems to be no comment about this "strange behaviour" in the documentation, neither in STM32G491 datasheet, nor in STM32G4 reference manual / at least I did not see anything...).

[MM..1]

Some years ago in galaxy ...

[flyer31]

Thank you :) ...

... but this difference STM32G473 to STM32G491 anyway is a BIT bizarre, as both STM32G473 and STM32G491 are new chips of same age as I see it... also from same family with identical Reference Manual... but the world is full of miracles :).