Decoding disassembled ICore

[vrocco]

I know that by removing the pin stacks from a SFIC type core you can determine the operating and control key from them. Can anyone point me in the direction of something that describes exactly how you dtermine this? Or give me a brief description of the process?

Also, I am interested in learning more about ICore locks in general. Can anyone recommend a good book or resource?

Thanks!

(If this is advanced, please move it there. I wasn't sure where decoding pin stacks would fall)

[jaysonbernard]

Here is an IC core Pinning sheet. With this you can work the math Backwards to come up with your keys.


A) __ __ __ __ __ __ -- Control Key Cuts
B) 10 10 10 10 10 10 -- Add 10 to get Control Number Below
C) __ __ __ __ __ __ -- Control Number ( control key cuts plus 10)
D) __ __ __ __ __ __ -- Top Master Key Cuts
E) __ __ __ __ __ __ -- Change Key Cuts

F) __ __ __ __ __ __ -- Bottom Pins(smaller number cut from CK or MK)
G) __ __ __ __ __ __ -- Master Pins(difference between CK & MK cuts)

H) __ __ __ __ __ __ -- Control Number From Line C
I) __ __ __ __ __ __ -- Bottom and Master pins (add line F & G)
J) __ __ __ __ __ __ -- Build up pins (Subtract line I from H)

K) 23 23 23 23 23 23 -- Total Stack Height (pre-set)
L) __ __ __ __ __ __ -- Control # (line C again)
M) __ __ __ __ __ __ -- Top Pins/Drivers (subtract line L from K)

N) 23 23 23 23 23 23 -- When all pins are added up they should = 23
/////////////////////
O) __ __ __ __ __ __ -- Top pins/ drivers (from line M)
P) __ __ __ __ __ __ -- Build up Pins (Line J)
Q) __ __ __ __ __ __ -- Master Pins (Line G)
R) __ __ __ __ __ __ -- Bottom Pin (Line F)


You would put your pin lengths in Lines O-R
Move them up to the Apropriate lines
Then take Line m and Subtract it from Line K
BAM you have the control #
Take 10 away from that and you have the control key cuts.
Just contine the same way and you will get the other keys.

[vrocco]

Good info. Thanks!

Ever consider putting that in an excel sheet. That way you could plug in values and it would do all the math.

I may tackle that if I get some time.

[jaysonbernard]

I have been tinkering with that for a while, but I'm not familar enough with excell to get it to do what I want it to.

[keysman]

Good info. Thanks!

Ever consider putting that in an excel sheet. That way you could plug in values and it would do all the math.

I may tackle that if I get some time.

Vrocco.......I sent you the link to EXACTLY that last week.. check your old PMS

[Raymond]

Determining the control from a disassembled SFIC is pretty simple. Just be careful when you lay out the pins not to bump or otherwise mix them.
You can do it the shortcut way by measuring just the top pin. IF all pin stacks were properly bitted and the total number is 23 then this works easily and quickly.
If the top pin is a 4 then the control is a 9 and so on.
4--9
5--8
6--7
7--6
8--5
9--4
10-3
11-2
12-1
13-0
This does not work if some paranoid locksmith pinned some of the stack to 22 just to screw up the person trying to decode the core.

The absolute way is to measure the bottom pins, master wafers and the control pin. Leave out only the top pin. Convert the bottom stack pin lengths to actual pin numbers. (.150'=#12, .500"=#4)
Add the bottom stack pin numbers. Subtract 10. TA DAH!
EX.: 7 bottom plus 2 master wafer plus 8 control equals 17. 17 minus 10 equals 7. 7 is the control cut at this space.

I made a chart that is taped on my work bench backboard that includes the micrometer measurement of the complete bottom pin stack. When I lay out an array of pins I just measure ALL of the bottom stack at the same time and do not have to convert.

Have fun.

[vrocco]

That sounds pretty good Raymond. Would you mind sharing that chart? I know I could go through and measure everything and make my own, but why re-invent the wheel?

Thanks!