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Topic: How to find JTAG or Serial ?

The content of this topic has been archived on 10 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

I got this router on Ebay,
It seems to work, at least the led blink but of course I cant surf with my provider
I'd like to flash it with Open-wrt but how I can find the Serial? or Jtag ?
Any suggestion ?
The image is available here:

http://www.postimage.org/image.php?v=aV1njYIA

Thanks

I would guess the 14 pin header near the top is JTAG and the 6 pin header in the middle of the board is serial.

Use a multimeter on the serial to find GND and VDD, then look for two other pins, one of which will be an input (so will show a much lower voltage than VDD, unless it has a pull-up resistor), and the other one will be an output, which will probably be VDD when idle.  Look for activity on the output when booting - if you get some, then hook up a serial adapter (make sure you have the correct VDD - it's usually *NOT* a +/- 12V RS232 port but more likely a 3.3V logic level port) and check various baud rates on boot to see if you can see the bootloader and kernel messages.

-- Rod

(Last edited by rwhitby on 11 Jul 2008, 03:22)

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