We have a PCB that is programmed via JTAG using the ST-Link/V2. Recently, I got some ST-Link Mini's, but I can't get them to talk to the same PCB the V2 does.

[BRich.3]

Looking at the pinouts for the 20-pin JTAG connector on the CBA being programmed, I see:

1 - 3.3V

2 - JTMS

3 - GND

4 - JTCK

5 - GND

6 - JTDO

7 - n/c

8 - JTDI

9 - GND

10 - /JTRST

11-20 - Odd pins are GND, Even pins are n/c

Looking at the STDC14 connector pinout for CN5 on the mini:

1 - n/c

2 - n/c

3 - T_VCC

4 - T_JTMS/T_SWDIO

5 - GND

6 - T_JCLK/T_SWCLK

7 - GND

8 -T_JTDO/TSWO

9 - T_JCLK

10 - T_JTDI/NC

11 - GND Detect

12 - T_NRST

13 - T_VCP_RX

14 - T_VCP_TX

So it appeared to me that if I just took a 10-pin to 10-pin cable, cut off one end, and replaced it with a 20-pin connector, still with pin 1 connected to pin 1, etc, it should just work. But neither STM32 ST-LINK (which is what we use with the /2 programmers, with an Olimex cable adapter) nor STM32CUBE seem to recognize the target CPU. If I swap back to the /2 with the 10-pin to 10-pin adapter, it works fine. Any suggestions?

[Tesla DeLorean]

>>Looking at the pinouts for the 20-pin JTAG connector on the CBA being programmed, I see:

That doesn't sound like a standard JTAG ARM connection used on the ST-LINK/V2, are you talking about the ETM Trace connector?

JTRST is not NRST

The 2mm 14-pin to 10-pin relationship on STDC vis ARM is the loss of the pair at each end.

[BRich.3]

Thanks. That was my initial thought, but I talked myself out of it for some reason. I think it was after I found this: https://1bitsquared.com/products/jtag-swd-10pin-to-20pin-idc-cable

But if I connect it the way you noted, don't I end up with JTRST connected to NRST anyway? Or are you saying "NRST" is an active-low reset, and so is JTRST? The 14-pin connector pinout came from the ST-Link "mini" document. ("Looking at the STDC14 connector pinout for CN5 on the mini:")

[Tesla DeLorean]

What I'm saying is your 20-pin enumeration is NOT for the ST-LINK/V2 header, and that JTRST is a completely different signal than the processors NRST