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Paralel
join:2011-03-24
Michigan, US

Paralel

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Edge Connector Interface On The Front Of The 3801?

Is anyone familiar with the edge connector interface on the front of the 3801 RG behind the face plate? I haven't seen one like it before. It's 7 pins, top and bottom, symmetric, five pins, then a notch, then 2 more pins.

I'm guessing it's a serial interface of some kind?

wayjac
MVM
join:2001-12-22
Indy

wayjac

MVM

Post a picture of the "edge connector"
Paralel
join:2011-03-24
Michigan, US

Paralel

Member

It's right above the Wi-Fi Protected Setup button:

This is the top:



This is the bottom:


wayjac
MVM
join:2001-12-22
Indy

wayjac

MVM

I was thinking this connector was exposed outside the enclosure
I'm not familiar with this
Paralel
join:2011-03-24
Michigan, US

2 edits

Paralel

Member

said by wayjac:

I was thinking this connector was exposed outside the enclosure
I'm not familiar with this


It is technically exposed, if you pop off the front face plate (plastic piece that says ATT at the top), there is an opening in the housing just above the WPS button where one could interface with this edge connector:



SomeJoe7777
join:2010-03-30
Houston, TX

SomeJoe7777

Member

My guess would be that it's a proprietary diagnostic port/connector used at the factory. As the units are being assembled, once they're all together except for the faceplate, a connector is plugged in here which can probably power up the unit and run internal self-tests. If the unit passes, they disconnect it, put the faceplate on, and box it.
Paralel
join:2011-03-24
Michigan, US

Paralel

Member

Crap. If that's true then it's essentially useless to anyone without knowledge of the pin-out and/or protocol.

I was hoping, since the 3800 had a simple internal serial interface the 3801 would have something similar. Apparently, no such luck.

SomeJoe7777
join:2010-03-30
Houston, TX

SomeJoe7777

Member

The protocol may be proprietary but maybe not. It may be serial or possibly JTAG. If you follow the traces from the pins and see what chip they go to, you can look up specs on that chip and get a pretty good idea of what the port does.
rsaxvc6
join:2011-02-21
Olathe, KS

rsaxvc6

Member

Truly proprietary electrical protocols are very rare these days. Then again, these units are a rare breed: very odd CPU:Trimedia, running a somewhat odd OS: RT-BSD

I will say the 3800 has a very similar edge connector, but I never figured out what it does. »www.flickr.com/photos/40 ··· 4587621/ Have you tried attaching an oscilloscope to it and see what happens on powerup?

Have you hunted for any other possible serial pins on the 3801? If you have large, highres shots of the board I'm happy to take a look.
rsaxvc6

rsaxvc6

Member

another unit I took apart also has this connector

»rsaxvc.net/blog/2011/08/ ··· own.html
RocketJeff
Premium Member
join:2008-08-20
Birmingham, AL

RocketJeff to Paralel

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to Paralel
Doing some quick searches, it looks like this connector is common on many 2Wire products.

People investigating it have found that it seems to be 2Wire's JTAG connector. They haven't been able to make a lot of use of it, from what I've found.

Here are some of the links I've found. Please note that most of them refer to different models and none of the references are to 2Wire units with firmware for U-verse. Play with them at your own risk:
Help Installing OpenWRT on 2Wire 2700HG-D
2wire 2701HG-G JTAG
bricked 2wire 2701HGV-w jtag help
asbokid
join:2011-09-12
n/a

1 edit

asbokid to Paralel

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to Paralel
Hi guys..

The same card edge connector is used on the 2Wire 2701 modem-router. These devices are re-branded and supplied by British Telecom.

I measured up the edge card connectors. It has 1.0mm (0.039") pitch or contact centres. As such, it is mechanically the same as the AGP and the PCI-express card. Although the card edge on the 2Wire PCB clearly has many fewer 'fingers'.

Maybe a connector could be fashioned using a PCI-E flexible riser by chopping off the female socket after the right number of fingers, but that's probably harder than it sounds!




Ideally, a cable would be made using the correct 20 way (2x10) 1.0mm (0.039") contact centre/pitch edge card connector from Sullins.




It seems that Sullins has an absolute monopoly in that connector. Here in Britain, it would cost £44 (~$80) to place a minimum order for them

http://www.sullinscorp.com/catalogs/41_PAGE08-09_1mm_DS_CE_SMT.pdf