Originally Posted by David1357
To give the opposing view, I will say that we have used Keyspan USB to Serial adapters for programming a wide variety of devices. We also use them under Linux for a wide variety of operations. We have never had a problem in either case.
Thanks for you replies.
I don't think that the problem come from usb serial converter. I tested it under some other boards and it worked fine.
I think that the problem come from JTAG.
Under windows, it is used to flash and to power the board.
If I try to use minicom, I must keep jtag connected to power the board. I think the problem comes from here.