Hi, Just upgraded the Keil 5.10 to 5.11 to have STM32L0 support.
When trying to debug my application I get: "st-link usb communication error" and debug fails.
I have no problem connecting to my board using ST-Link Utility.
The 5.10 works fine - no issues with connecting to the ST-link.
I use the latest ST-link drivers and firmware (STLinkUSBDriver.dll v4.3.3.0, ST-LINK Firmware version : V2J21M5)
Bogdan
Thanks for a great advice guys. Indeed, downgrading from V2.J21.M5 to V2.J20.M4 solved the issue. I am using ST Nucleo F401RE with STM32F401. Just for the convenience of others, if your Keil root installation folder is C:\Keil_v5, then you will find out the previous version of the firmware for ST-Link in your Keil installation under C:\Keil_v5\ARM\STLink.
Nice!
Hi, i have 32F429I Discovery kit and when i upgrade from V2.J20.S0 to V2.J21.S0 it stop working and message "USB communication error" when trying to load in uVision always shows up. Downgrading to J20 helps! (Just run the STlinkupgrade in the directory in previous post) Thanks guys!
Hi All, I am encountered the same problem above and with the old Firmware on ST-Link it works.So I downgrade it.