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Topic: GN-B41G high resolution photos of circuit board

The content of this topic has been archived on 3 Feb 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.


I opened up my GN-B41G and took a few high resolution photos of the circuit board.
Bottom side
Top side
Top side, MiniPCI removed
(MAC and serial numbers intentionally blanked out)
There is a sticker on the flash memory. The part# under the sticker it looks like Am29LV160D. That's 2MBytes.
The SDRAM is on a 32bit databus and is 16MBytes in size.
I would love alternative firmware support for this router. IPv6 support would be really nice.

I'am a programmer and a hardware engineer working full time developing TCP/IP and other protocol stacks for embedded systems, but unfortunately my linux experience is very limited.


There is a 20pin header on the board. Looks like a standard pinout 20pin JTAG header to me. JTAG ICE debug support will of course help any development efforts.

The unmounted connector (CON1) could be a serial port, but from the looks of things I'd say it is more likely a alternative power connector. It could of course be a combined serial port / power connector.

(Last edited by Nikon on 22 Sep 2005, 06:34)


If you're a hardware engineer, you might want to measure the voltages on the pads of CON1, since 4 connectors are enough to get a serial connection.


True, but even if it is a serial port, it would not be enabled.
Notice the missing FB3 and FB4 components near the main CPU. R412 and R413 are also missing (near the connector). It would be necessary to replace theese missing components with a small piece of copper wire or something.

There is also no RS232 transciever on board, so the signal levels of any serial port would be 3.3Volt logic levels (need external RS232 transciever to connect it to a PC).

(Last edited by Nikon on 15 Nov 2005, 23:39)

So, what's your conclusion here? Is it possible to get OpenWRT onto these? Anyone working on it?

CON1 looks like an USB connector to me... this would also explain the fuse "parts" that are not soldered.

Do you even know if this router is running linux?  If CON1 is indeed a USB connector, perhaps you're in luck if you could find a way to get console output from it.  Does gigabyte offer source for this router?  How do you know it's not running vxworks?

Next step?

Find out what architecture it's running on and see if there's a similar manufactured router that's already running openwrt.

This should be easy enough since the source is available.

Often times, despite different vendors, the reference design of the board will match very closely on similar chip manufacturers since they're following the oem's recommended reference design optimized for their chip.

If source is being provided, you should also be able to find out the default password for access.  Have you done a port scan to see what ports are open and what services are running on them?

The key is the architecture.  Once you figure out what chipset it's running on, you not only have the pool of GN-B41G hackers and info out there at your disposal, but all the other open sourced routers running the same chipset and their persistent owners to draw on.  I'm sure you'll be able to find a match.

If at first you don't succeed, keep on sucking until you do suck seed.

SaTaN: I agree, most likely a USB connector.
Probably of little use for debuging purposes since USB is kind of complicated to get up and running. If you have USB running, then you probably already have ethernet up and running as well. It could of course be a interesting feature for other purposes, like connecting a USB mass storage device for extra storage space, or adding a Bluetooth dongle for connectivity to a mobile phone.

The processor used in this router is a ARM940T-based Samsung chip called S3C2510A. Everything but the WLAN is integrated into this chip. Seems to be fairly common.
Everything you may want to know about it, including a complete datasheet/manual can be found here: … C2510A.htm

Check out this discussion about routers using this Samsung chip:

(Last edited by Nikon on 22 Jan 2006, 00:56)

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