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Scott Löhr
Senior III
November 18, 2021
Solved

B-U585-IOT02A board CN5 cable to ST-LINK?

  • November 18, 2021
  • 8 replies
  • 3085 views

What is the part number and/or where can I buy a cable from the ST-LINK to the B-U585-IOT02A board CN5?

As a tangential question, why in the heck didn't ST just populate CN5 with a male 4-pin?

(I'm a firmware guy, I don't solder, well, perhaps until now ... hope I don't damage the board trying)

Seriously, what a pain to just getting started with this board.

This topic has been closed for replies.
Best answer by Scott Löhr

And following the pinout shared by @Uwe Bonnes​ above, I jumper-wired an ST-LINK/V2 to CN5 as follows:

P1-to-P1

P7-to-P4

P9-to-P2

P10-to-P3

Note that I chose the P10 GND out of all of the possibilities because it is the GND used for the SWIM connector as well (so just a hunch that it would be the single most "grounded" GND of the all).

And to note that my suspicion about the mis-information in UM2839 section 7.8.2 is correct - the answer is that you have to jumper-wire to the CN5 and power the STM32WB5MMG RF module by CN12 with the SW3 moved to appropriate position, or power the STM32WB5MMG RF module by board power with the CN8.

8 replies

Scott Löhr
Senior III
November 18, 2021

UM2839 - Rev 1 is missing information on the pinout of CN5, it is not found in section 7.8.2. Furthermore, it seems that the information is incorrect: "Using CN5 SWD or SN12 USB connectors as shown below, Bluetooth Low Energy module firmware can be updated." I do not see an ST-LINK embedded with the CN12 connector, nor do I see one enumerate when plugging the CN12, regardless of the SW3 position and regardless of whether the whole board has power from CN8. It would seem that the instruction should be "Using CN5 SWD and SN12 USB" to program the STM32WB5MMG RF module, so you will need to power the WB by the USB CN12 AND find a way to jumper-wire the ST-LINK to the CN5 pins ... but how, please?

Uwe Bonnes
Chief
November 18, 2021

CN5 is a normal 2.54 mm Pin Header. Use 4 wire jumpers if you find nothing better.

Scott Löhr
Senior III
November 19, 2021

Spacing of holes is 2.54 mm, diameter of holes is too large for breadboarding jumper wires, so soldering is necessary.

Uwe Bonnes
Chief
November 18, 2021

The pinout is the "normal" ST SWD pinout 1 = VCC, 2 =SWCLK, 3 = GND and 4= SWDIO as found on DISCO and Nucleo Boards/

Scott Löhr
Senior III
November 19, 2021

@Uwe Bonnes​ - thank you, that is the pinout.

Scott Löhr
Senior III
November 19, 2021

So, I had to break my soldering cherry today, since ST saved a few pennies by not including a 4-pin male header for CN5. I've always had somebody in office I could go to for soldering favors, but since working from the home office, that is not an option and I had a soldering iron stashed away for an absolutely urgency like this. As you can see, working from top to bottom, my skills improved after just 4 tries. Actually, that 4th one looks pretty good for a firmware guy if I don't say so myself.

Scott Löhr
Scott LöhrAuthorBest answer
Senior III
November 19, 2021

And following the pinout shared by @Uwe Bonnes​ above, I jumper-wired an ST-LINK/V2 to CN5 as follows:

P1-to-P1

P7-to-P4

P9-to-P2

P10-to-P3

Note that I chose the P10 GND out of all of the possibilities because it is the GND used for the SWIM connector as well (so just a hunch that it would be the single most "grounded" GND of the all).

And to note that my suspicion about the mis-information in UM2839 section 7.8.2 is correct - the answer is that you have to jumper-wire to the CN5 and power the STM32WB5MMG RF module by CN12 with the SW3 moved to appropriate position, or power the STM32WB5MMG RF module by board power with the CN8.

IVent.1
Senior
December 13, 2022

Hallo...please, I connected the stlink to CN5 using the 4 pins connector of the stlink, and I powered the u585 board using CN8 connector, but cube programmer shows me only the main mcu, stm32u575 and not the stm32wb. What else I have to do? thank you