https://devzone.nordicsemi.com/f/nordic-q-a/13327/rtt---slow-erase-program-cycleI just started using the RTT - It&#39;s proven to be a VERY helpful debugging tool. As soon as I started using it I located several minor bugs. I exited debug mode, fixed the bugs. After compiling, when I clicked Keils debug option, which erases and reprogramsen-USTelligent Community 13Wed, 20 Apr 2016 01:23:59 GMThttps://devzone.nordicsemi.com/thread/50809?ContentTypeID=1Wed, 20 Apr 2016 01:23:59 GMT137ad170-7792-4731-bb38-c0d22fbe4515:386640c3-bd19-4bd7-a5b2-bd2035b90980Tien<p>Hi, c cook RTT viewer need a Jlink process to get the log data. When you select the USB connect mode, RTT viewer will create a new process to do this. The problem is when you start download or debug the chip, another new process will be created too. And they are all trying to connect the only one JLink device, it will be very slowly.</p> <p><img src="https://devzone.nordicsemi.com/cfs-file/__key/communityserver-discussions-components-files/4/8666_2E00_.PNG" alt="image description" /></p> <p>If you used to view the terminal when debug the chip, you should select the Existing Session mode.</p><div style="clear:both;"></div>