Hi there! I'm really stuck! I tried the guide with a usb to TTL, i got the adapter to work (through the loopback test) i connected my ST3500320AS with the adapter terminal is working ok, i got the Z (spin down command) working ok BUT when i remove the card and press the U command nothing happens! I tried with the card and i also tried removing the pcb, then connect again to run the U command but same resolt, Nothng! Can anyone help me?