WDTVLiveSerial

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3.3V TTY Serial Port

If your WDTV is bricked, you will most likely need to interface with it through the serial connection on the motherboard.

To do this, you will need a 3.3V TTL-Serial cable. I use an adapted Nokia CA-42 USB to TTL-Serial cable, but you can use whatever cable you want/have.
These little serial cables come in handy when working on embedded boards like this.
Here is some information on how to make a CA-42 into a USB to TTL-Serial cable.
The wire colors may be different, so be careful!

OR

You can also get one here which is cheaper and only has the 3 wires inside you will need to interface with the serial connection on the WDTV (RX, TX, and GND).
It comes with a driver disk that will allow Windows to recognize it when plugged into your USB port

NEVER CONNECT THE WDTV SERIAL PORT (3.3V) DIRECTLY TO YOUR PC's SERIAL PORT !!

WDTV Live/Plus serial port

You only need to connect the RX, TX, and Gnd. NOT THE 5Volt pin. BE CAREFUL!!

  WDTV circuit board |     CN4 pinout
                     |    .---------.
                     |    | o o o o |
             CN4     |    '---------'
          .------.   |      ^ ^ ^ ^
          | .... |   |     /  | |  \
          '------' O |   +5V RX TX GND
'--------------------'


WDTV Live Streaming (Gen3) serial port

You only need to connect the RX, TX, and Gnd. NOT THE 5Volt pin. BE CAREFUL!!

  .-------.        .-----------.
  | ..... |        | o o o o o |
  '-------'        '-----------'
--------------       ^ ^ ^ ^ ^
    front           /  | | |  \
                   RX GND|GND TX
                        +5V   


Making the cable

In order to interface with the serial connector, you will have to modify the connection end. Cut off the phone end and add a 4 port serial connector end. I used a cdrom audio cable connector end (the cable that delivers audio from a cdrom to the motherboard on a PC.). It's a 4 pin end that with a little bit of exacto knife work, fits nicely into the WDTV serial interface connector.


Confirming RX, TX, and GND

If you have the 3 wire cable, you just need to determine which wires are RX and TX and which is GND. To do this you can open a telnet session (see instructions below) and connect 2 wires together until your keyboard strokes are returned in the console. The 2 wires that return your input are RX and TX, and the 3rd wire is GND. If you have more than 3 wires you can use a multimeter to determine the cable that carries the 3.3V. You only need to connect RX, TX, and GND.


Telneting to the WDTV

Eventually you will need to interface with the WDTV board using a telnet program. I used Putty to do this. You will need to determine what COM port your USB cable is using. With the cable connected, you can find this information under the USB area in Device Manager (Windows OS).
Start up putty, and from the Session screen click the Serial radio button, enter the COM port the USB cable is connected to in the Serial line box, and change the Speed to 115200. You also will want to turn on logging, by selecting Logging and clicking the All session output radio button. When everything is configured, Click Open to start the session.


COM port settings

Speed 115200
Data 8
Parity None
Stop 1
Flow Control None


Tips

  • When connecting the TTL cable try reversing RX/TX if you don't get the console.
  • You can remove the top cover by pulling on it firmly to expose the inner PCB. Details in this video by b-rad: http://b-rad.cc/binaries/WDTV.Shell.Removal.AVI


Reference threads


--Recliq 13:43, 10 July 2011 (UTC)