08-23-2025, 09:49 PM
I ran into the same problem. I had to make sure the board (NodeMCU-32S) was in bootloader mode. To do that, hold the "download button" on the KC868-A16S, then press and release the "reset" button. Then, while still holding the download button, I began the upload in Arduinio IDE. I waited to release the "download" button until I saw the output of Arduino IDE say "connecting". Then release the download button. This sets the processor to the bootloader and will then take your sketch. Once I did that, it uploaded correctly and worked really well.