V3 MINIE not working with U575 custom board

[WellLeithed]

I have a 14-pin connector and a 6-pin fall back connector. I can connect the 6-pin SWD via st-link V2 on a nucleo board but I cannot connect with a V3 MINIE on the 14-pin. Any ideas? I followed the schematic for a 14-pin connector I found on a NUCLEO board, which had a 100 ohm resistor on GND detect. I have bypassed it but the result is still the same. Apart from that and the TX/RX, the wires are the same for the 6-pin connector that works?

Here's my output:

CDLiveWatchSetup
Info : auto-selecting first available session transport "hla_swd". To override use 'transport select <transport>'.
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
Warn : The selected adapter does not support debugging this device in secure mode
adapter speed: 24 kHz

none separate

Info : Listening on port 50004 for tcl connections
Info : Listening on port 50005 for telnet connections
Info : clock speed 24 kHz
Info : STLINK V3J14M5 (API v3) VID:PID 0483:3754
Info : Target voltage: 3.272000
Error: init mode failed (unable to connect to the target)

[TDK]

Can STM32CubeProgrammer connect?

If not, probably a wiring mismatch or bad connection somewhere.

It detects voltage, so that part is good.

[WellLeithed]

It can't, although I connected my MINIE V3 to a nucleo board so that's not the problem.

I followed this schematic (https://www.st.com/resource/en/schematic_pack/mb1549-u575ziq-c03_schematic.pdf) but the 100 nF capacitor on NRST doesn't seem to go to zero when I connect the debugger. It gets to about 1.8V. One thing I didn't do is add the ESD protection.

[TDK]

When the board is connected to the MINIE V3, how is it powered? The programmer does not provide power.

[WellLeithed]

Yes. With a battery. The power is stable.

[Andrew Neil]

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@WellLeithed wrote:

I have a 14-pin connector and a 6-pin fall back connector.

Please show the schematics.

How to write your question to maximize your chances to find a solution

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@WellLeithed wrote:

I can connect the 6-pin SWD via st-link V2 on a nucleo board but I cannot connect with a V3 MINIE on the 14-pin.

What about the other combinations ?

	14-pin	6-pin
st-link V2	?	OK
V3 MINIE	fail	?

PS:

Can the V3 MINNIE connect to anything else?

[WellLeithed]

 

I copied the nucleo schematic I linked earlier.
As I mentioned the MINIE is fine as I connected to nucleo board and visualised it on CubeProgrammer. 
I cannot complete the table as I'm unable to connect the parts in the manners suggested.

[WellLeithed]

And here's the 6-pin connector.

[TDK]

Schematic is okay. Maybe the footprint on the connector is wrong, or it's installed in reverse.

[Andrew Neil]

Or an error in the wiring between the ST-Link and the connector ...

Can the V3 MINNIE connect to anything else?