Monday, March 28, 2011

New pics from my decapping project

In the first two pics you can see the damage been made by the drill i used. Only a fraction has been revealed with the drill and the rest was made with nitric acid.
Both of the mcu's were damaged because i used a small tweezer to clean up the excess debris without the ultrasonic cleaner.
Lesson learned: No more tools inside until the whole wafer is exposed. I have to be careful with the drill too.

Friday, March 25, 2011

VX-8R docs

Seems the ham community missed the VX8 series radios.
Most of the sites are not updated regarding the user or service manual or the device. Lack of info around the handheld is 90%.
Wtf happened with this one? In the older days people people were building projects around handhelds or torn it apart to mod it etc.
Maybe Yaesu has been left behind a bit. If i could design a handheld i would make sure to have a USB interface for a PC, maybe pack as many features i can inside,  remember times have changed, people use computers for everything and the market tends to work near computers.
One of the problems i see is that they do not use new technology very efficient by using old parts or complicated designs, yes they are reliable as hell but radios lack of some features that in the newer days are mandatory.
Someone might say "if you pack too many features inside then the handheld won't be reliable or will have crappy performance"
Not true, newer designs can use far more reliable parts and circuits. Newer microcontrollers (like the PIC32 etc) can offer more but the manufacturers still choose small ARM architecture MCU's.
Then there is the problem of copyright and FCC etc, but anyway if someone wants to copy or mod  a design he will do it no matter what, remember the nokia BB5 series? They "used" to be the most secure platform and now it's an every day unlock.

Sunday, March 6, 2011

MCU decapping for live analysis

I was decapping some PIC MCU's lately (PIC12F629, 18F4550, 18FC452, 16F876A, 16F84 etc) for live analysis. Mainly for training my hands on and some security bits erase.
I got the ideas from Sergei Skorobogatov's page and Bunny's blog the first one is one of the best sites i've ever seen on MCU security.

So i started.

One thing  was annoying was the YELLOW light from the stereoscope lightbulb, so i thought i change the bulbs with newer technology LED ones.
I purchased from ebay for about 2$ two festoon 36mm led lamps and plugged them in.
Surprise suprise!! The stereoscope has only a transformer without any other circuits and the led was only flickering at 50Hz. Damn!
I made a quick perforated board power supply with filtering using the 78S12 regulator and presto.
Note: Images show only the under side of the scope (which i do not use). There is also a LED lamp above. You can see part of the board with the regulator and heatsink (when you have the led's on it's barely some degrees over room temp).
I like it, now i can proceed!

I'm using a drill to create the first pit and to eat away most of the black rosin from the chip and then i use 70% Nitric Acid to burn through it. Nitric acid works best when heated around 70% and i found out that my pcb preheater works fine for this.

Stay tuned for more.