STM32Wl55CC connection error for SWD programming

[georgerambak]

I am trying to make a prototype from a perf-board and a QFN48 adapter using STM32WL55CC MCU based on the wiring in the pics below.  I want to connect to the MCU using SWD via an STlink attached to a Nucleo board. I already removed the 2 jumpers on CN2 and made the following connection shown below to CN4 and the MCU. However when i try to connect using the ST-Link utility I am getting the following error. BTW I just started learning embed development and just want to connect via SWD for now. 

Connection Details:

VDD_TARGET(PIN1 on CN4)=>3.3V supply from PIN16 CN7 on the nucleo board

SWCLK(PIN2 on CN4)=>PIN 42 on STM32Wl55CC

GND(PIN3 on CN4)=>ground pad on STM32Wl55CC

SWDIO(PIN4 on CN4)=>PIN 36 on STM32Wl55CC

NRST(PIN5 on CN4)=>NRST on TM32Wl55CC

VDD for the MCU is supply from 3.3V CN7 PIN16 of the nucleo board

[TDK]

What about all the other power connections? RF and SMPS? These do not seem optional even in LDO mode.

https://www.st.com/resource/en/datasheet/stm32wl55cc.pdf

Consider buying a known good board for development. Having decoupling caps so far from the chip is not ideal.

https://www.st.com/en/evaluation-tools/nucleo-wl55jc.html

[georgerambak]

Thanks for the feedback. Based on the reference design documentation (see pic) I came to the conclusion that the RF and SMPS are not needed for just connecting via SWD for programming. Also the I am using the MB1789_LP-LowBand_LowPower reference design as a guide. I did not use a Nucleo-Wl55 development board because I eventually will need to develop my own board if I am to deploy anything serious and I want to delve deeper into the hardware development side.