Rather than try to describe your circuit in words, please use a schematic - it's far clearer.
You also need some decoupling caps.
See the datasheet and AN4467 for power supply connections.
https://www.st.com/resource/en/datasheet/stm32l031k6.pdf
https://www.st.com/resource/en/application_note/an4467-getting-started-with-stm32l0xx-hardware-development-stmicroelectronics.pdf
@LubO_o wrote:
From what I read online I can pass without the external crystal because there is an internal one.
Correct (although, strictly, it's not a crystal - it's an RC oscillator)
@LubO_o wrote:
when I connect the VDD to 3v3 on the st-link
What ST-Link do you have?
Note that a genuine ST-Link does not provide power to the target
See: How to recognize a genuine ST-LINK/V2 versus a cloned one
In particular: https://community.st.com/t5/stm32-mcus/how-to-recognize-a-genuine-st-link-v2-versus-a-cloned-one/tac-p/703663/highlight/true#M965
PS:
@LubO_o wrote:
the chip isn't recognized.
Using what tools?
Show any error messages & logs you get.
Note that keeping your wiring short & tidy is important. Wiring should be kept short, neat, and direct - with the minimum of joints.
Be particularly wary of solderless breadboards, cheap "dupont" style headers, etc:
https://community.st.com/t5/others-hardware-and-software/quot-no-device-found-on-target-quot-trying-to-flash-xm125-radar/m-p/782641/highlight/true#M31139
More tips on resolving debugger connection issues here:
https://community.st.com/t5/stm32-mcus/how-to-solve-debugger-connection-issues/tac-p/698105/highlight/true#M956
A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.
