hello, how to program a STM32L151CBU6 without using JTAG?

[MLemd]

I use STM32CubeMX and IAR Embedded workbench. I find to test IAR example projets, but i get this error:

Fatal error: Cannot connect to J-Link via USB.  Session aborted!

[Tesla DeLorean]

You have a J-Link, not an ST-LINK?

The device is actually powered and functional?

What exactly have you wired up? Can you provide a schematic, or partial one?

With BOOT0 High the device will go into the System Loader, where you can try to connect via USART or USB, etc as supported. See App Note AN2606

https://www.st.com/content/ccc/resource/technical/document/application_note/b9/9b/16/3a/12/1e/40/0c/CD00167594.pdf/files/CD00167594.pdf/jcr:content/translations/en.CD00167594.pdf

Make sure VDDA is powered, check level on NRST. Check part orientation.