Pin 1: VDDH (3.3V)
Pin 2: TxD
Pin 3: RxD
Pin 4: GND (Ground)
There are third-party vendors who provide compatible console boards, such as the
AD233AK/AD233BK RS232 adapter kits at:
http://www.compsys1.com/workbench/On_top_of_the_Bench/Max233_Adapter/max233
adapter.html
Make sure the third-party adapter board is connected correctly to the corresponding pins
of J303 on the router board.