I have a setup where I run some tests on a NRF52840 board automatically, and I automatically capture and save the SWO output to a file using the command line SWO viewer. Recently I tried to set up a new computer to do the same thing, but the new computer has an issue. The issue is that a few very specific values at the end of the output have ÿ instead of the numbers that should be there. If I run SES while I have open the SWO Viewer, I can see the correct output in SES, but swo viewer, like the swo viewer command line tool shows a different output. See the image below. This y with the dots on top is unicode 0xFF. But I can't figure out why its there. I have tried a jlink base and a jtrace pro and they both have the issue. I have tried all different frequencies for the capture in the viewer. They all have the issue. And the weirdest part is the issue of the y's done not happen in any other part of the output, just at the end.

I have v7.22 of the tools. I tried 6.60 also just to see. same issue. I also realize the the SES output I showed is really debug output from the USB port that we print also. So it is supposed to be the same as the SWO output, but is not actually coming from the SWO.

OK nevermind It is not the swo viewer that is the issue. Sorry Segger. Stepping through the code I see the the code is sending hte value of 0xFF. I am not sure why this computer is different from my other computer, maybe different compiler version, but thats not you issue. Thanks for letting me vet. Feel free to delete this or mark resolved. I cant see how to do either.