Quick thought - are you trying to connect to the Bangle.js (or similar) in nRF Toolbox, rather than DfuTarg?
@ajkm started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Quick thought - are you trying to connect to the Bangle.js (or similar) in nRF Toolbox, rather than DfuTarg?