Postby ArT » Wed Oct 18, 2017 12:14 pm
In case when you need to use external power supply than you should connect external power supply before operation. You need to make sure that connections (from programmer) are correct before power on external power supply (wrong connections may damage programmer because power goes from external circuit). Some motherboards execute start up procedure (bootloader) and after connecting power supply communication bus is busy - in such case you need to wait for bus idle (sometimes it is few seconds, sometimes it may be even 2 minutes) otherwise you will have bus conflict and communication error. When you use external power supply it is recommended to set the same voltage level in programmer (you can adjust it with 0,1V threshold selecting user voltage).