How to enable vcom function before connect target with swd.

Hi,

Quote from tinydrop

I connect target device with swd (7pin 9pin 2pin)

It should be:
7 - SWDIO
9 - SWCLK
1 - VTREF (not 2)
5 - J-Link-Tx (J-Link out => Target in)
17 - J-Link-Rx (J-Link in => Target out)
One of the pins you mention is wrong.

If this does not fix the issue:
Could you please check the following?
https://wiki.segger.com/Using_J-Link_V…ality_and_speed
If the self test works, the issue lies on either
- the connection between Target & J-Link (Faulty cables, Wrong pins connected, ...) o
- on target side (wrong pins toggled, no data send, ...)
We advise to use a Oscilloscope for signal verification.

Could you please check?

BR
Fabian