Transition from NUCLEO board to custom PCB

[Yiftah]

Hi,

I'm currently using the NUCLEO-G071RB.

I want to design a custom PCB including only the STM32G071RB MCU and a PMIC (without the STLINK part of the NUCLEO board).

1. Is the STLINK/V2 compatible for replacing the STLINK part of the NUCLEO? Are there other devices which are compatible?
2. I noticed the STLINK/V2 has different cables with different connectors. None of the connectors has STLK_RX, STLK_TX & MCO. Which one should I use?
3. Is there a guide document for this transition from NUCLEO board to a custom PCB? What components are critical to keep on the PCB and what can be removed?

Best regards,

Yiftah

[Uwe Bonnes]

1. A standalone STLINK/V2 does not provide UART and MSD functionality
2. There are zillions of debug connectors
3. The STM32 devices resource pages often have some hardware document. What is critical and what can be removed depend on your requirements.

[Yiftah]

Thanks for the quick reply.

1. If I'm only looking for flashing and debugging capabilities is the STLINK/V2 enough?
2. Sorry, I was referring to the list of options in the STLINK/V2 datasheet. In the datasheet it says: "For development of applications based on STM32 microcontrollers the ST-LINK/V2 needs to be connected to the application using the standard 20-pin JTAG flat ribbon provided". But there are only 6 different signals on this 20-pin cable (VDD, GND, TMS, TCK, NRST and TDO). and TDO signal does not appear in the NUCLEO board schematics. Why can't I use a cable with only 5 pins?
3. OK, I will continue searching.

[TDK]

I'd recommend the STLINK-V3MINI or STLINK-V3SET as they're faster and more likely to be supported in the future.

Only pins you need are SWDIO, SWCLK, GND, NRST (optional but recommended), and VDD_DETECT (optional but recommended).

You can use a 5 pin cable. However, using a standard connector means you won't have to create a custom cable to debug your board.

[Nikita91]

What standard connector ?

On old nucleo = 6 pin inline,

On new nucleo 10 pins dual inline 0.05"

STLINK V2 20 pins 0.1"

STLINK V3 14 or 10 pin 0.05"

Chinese STLINK 4 pin 0.1"

???

[Tesla DeLorean]

You can uses whatever cable and pin arrangement you want.

The ARM standards are for a 10 or 20-pin connector, of which a subset of pins are used.

ST has an assortment of implementations, including a 14-pin variant of the 10-pin ARM connector, including UART RX/TX.

The UART connections isn't necessary, but CM0(+) parts don't support the SWV/SWO communications channel.

The MCO is a clock source to provide 8 MHz to the target without additional parts. Design with your own HSE clock if you are doing USB/CAN applications.