Hello there is an missing explanation on user manual at page 12. Because there is no ground (GND) connection on pin 4 of the CN3. We have also STLink v2. We connected same pins to STLink v2 ISOL for SWD (we are using CN3-4th pin for GND) but cannot connect to target board then check the connections of pins and saw there is no connection to GND on pin 4. Can anyone change that on manual to indicate the difference (we didn't find, there is just indication for pin 19). Because we spent 2 hours for that and started to think about the debuggers are faulty.