Rev 4 is alive. Today I have soldered new version of the board, arm bridge received it's own crystal and now it is 100% separated from sd card and can be used simultaneously. Also it has its own 4 bit gpio port and led. TVS diode caused too much drop on usb power so I decided to use it in reverse polarity to ground still being reasonable protection for overvoltage and reverse current. Next step is to create fully arm bridge example - usb keyboard host and simple text browser on ILI9341 display.