Hi, Thanks for the answer. I’m using a Linux host (I installed Ubuntu Dekstop 18.04, alongside with 20.04 and 22.04 to test them all). Yes I selected Seeeduino Zero and port ttyACM0 before uploading. Thanks for the link but I can not find the location of these RST and GND pins: where are they located in the Odyssey X86i51135G7 ? The picture shows it for the X86J4105/ X86J4125, which have not the same layout as the X86i51135G7 that I’m using…