Hi Kenny,

I have configured things to use Semihosting + SWO Output and it works

Semihosting and SWO usually exclude each other, so only one is active at the same time (since both are usually used for printf())
Semihosting and SWO are totally different technologies. (I know that it might be presented a bit irritating in IAR EWARM)
In your case, I assume that you are using SWO.

The problem is that each time I enter a debug session it doesn't remember to enable ITM port 0 and direct it to the terminal window. Is this a JLink or IAR issue? Basically Port 0 is unchecked in the SWO Configuration window.

This dialog is completely provided and maintained by IAR EWARM.
J-Link has no influence on the settings shown / being available in this dialog.
This is more something for the IAR support / forum than for ours.

Anyhow, for printf there might be an interesting alternative for you:
SEGGER RTT (segger.com/jlink-real-time-terminal.html)

Also works on M0 targets which do not support SWO at all.
Moreover, you do not need an additional pin, nor need to battle with the frequency issues SWO comes with... (sender + receiver need to use the same frequencies etc.)


- Alex