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mschuster91
Are there maybe some JTAG lines exposed on the board?

Maybe these could be used for finding out the contents of the mem chip and the CPU used.

q3k
This class of devices is often made at a ridiculously huge volume and the cheapest way possible, so they're very likely to contain one-time-programmable devices with no test / debug lines.
mschuster91
Yet there are labeled(!) test points visible for the I2C lines on the board, and a number of other labels... so the question is, why doing the epoxy stuff while leaving the labeling on the PCB?
duskwuff
Epoxy blobs tend to be more about cheap mass-production than anti-reverse-engineering. If you're getting a custom chip manufactured, it's often easier to just stick the die straight on the board than it would be to have it put in a package, then put on the board.
mschuster91
How is the bonding from the pads on the die to the pads on the PCB accomplished? Sounds easier to do with packaging compared to PCB for me.
csmuk
Exactly the same way the die connects to the pins on the package (usually fine wire). Then they cap it all.
ChuckMcM
Epoxy enhances reliability by keeping the chips hermetically sealed. So when your kid barfs on his favorite Furby it still has a chance of working, or gets thrown by the family dog against the wall.

They are fun to play with from a hardware poking perspective.

rhgraysonii
It's projects like this that spark me to always go out and try to learn new things. I forget how much of our surrounded world is hackable sometimes, and it really is sad to think I get so caught up I don't think of these projects near as often as I used to. Hopefully this guy gets somewhere :) these writeups are inspiring, interesting, and educational all wrapped into one nice little package.
tumes
"A Furby is an evil robotic children’s toy wrapped in colored fur."

If only all technical reviews started this honestly...

shabble
Whilst some impressive hacks (and especially convincing university staff to lend you their Expensive Toys), my understanding is that the really tricky bit is going from die scans to netlist/circuit diagram, and thence simulation/code extraction.

The Visual6502[1] folks are probably the best example of how well it can be done (assuming you can't afford to pay ChipWorks or FlyLogic to do it for you), but if you're working with a standardish MCU core and some masked ROM, a lower tech solution like the Dangerous Prototypes "rompar"[2] might work.

Probably requires quite a few dies, or plenty of experience in extracting them before you succeed though.

For actually reverse engineering the flash contents, I think it'd be easier to sniff the bus traffic as you probe it, or make a read/write capable emulator that logs what's going on. With the hacked phone-side control library, you could probably build a mostly automated harness to exercise the various settings and see what gets stored in flash.

[1] http://visual6502.org/

[2] http://adamsblog.aperturelabs.com/2013/01/fun-with-masked-ro...

userbinator
Coincidentally it's very likely the new Furby also uses a GeneralPlus 6502 (CMOS) core.
glifchits
Just funny to think that its possible that a dev who hacked on that Furby firmware is reading this and said "hey, I wrote that routine!"
agoandanon
So, remember that virus that communicates using high-pitched sound? If no, here's an article:

http://arstechnica.com/security/2013/10/meet-badbios-the-mys...

This article says that the Furby communicates in the same way. It would be interesting if the Furby was a vector for spreading messages via this virus. Very, very interesting.

mschuster91
I doubt this (Furbys are kiddy toys, after all); but this article proves that audio is indeed a viable data communication channel for bypassing air-gaps.
Juno5143
lets ban audio
bigiain
"Furby: Approved for use in non-pressurized compartments of the International Space Station (only)."
fphhotchips
New security measure, from now on I will only allow our user to use their PCs in this room.

http://blogs.smithsonianmag.com/smartnews/2013/12/earths-qui...

superuser2
If anything, data over audio would be easier in an anechoic chamber since you don't have to worry about reverb or background noise.

US Military guidelines do require acoustic isolation of all SCIFs (Secure Compartmentalized Information Facilities). You just need isolation, though; deadening the rooms is not really necessary.

jrockway
Someone should invent some sort of general modulator/demodulator and use sound to connect computers to the Internet!
adestefan
Not sure if this is sarcasm...
girvo
Oh come on, calling it a modulator/demodulator totally gives it away :)
adestefan
I like to give the benefit of the doubt but in general I just don't trust comments on HN anymore.

Plus doing it with light is just way cooler.

drpancake
From the Wikipedia article: "Furbies were banned from the National Security Agency of the United States due to concerns that they may be used to record and repeat classified information."

http://en.wikipedia.org/wiki/Furby