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How to unlock the 8051 lock bits without interrupting the code?

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scientificpakistan

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Dear Forum Members,

Is there any software, or any way to unlock the 8051 lock bits without Interupting the code.
 

how to lock 8051 coad

Hi,

I think that there is no regular way to access locked code.
 

zigzag2000@126.com

Compare the lock bits to fuses: once they are burned that's it ..

From our perspective it is rather uneconomical to try to read the code of a microcontroller with burned lock bits, althogh there are "smart arses" out there who claim thay can do it ..

Regards,
IanP
 

8051 lock code

hi.

here in india i am running a small development firm. almost always the first question i get from my client is how to get the code from locked 8051.(or some other uc). so i have to convince them that it is impossible officially, and if also it possible it will cost a fortune. in the fraction of a cost we can really build it and put the project for production.

so the best thing is to get the complete project where the uc(in this case 8051) is working properly and ovserve the functions of the project and write it down. and then try to build the project yourself. you already got the hardware idea. only have to program accordingly,

its very easy to work out in this way.

arnab/vu2bpw
 

manufacturing companies of 8051 in pdf

thx
 

breaking 8051 lock bits

Hello Guys,
Here is a VERY OLD and OUTDATED pdf file including code on how some really old locked 8051's were read. Now this will never work in a million years on a newer 8051 but I thought it was interesting reading, enough to post it here.

I did however SEE with my own two eyes a company that read a locked 89C51RD2 in less than one second.

It may not be that easy for newer 8051's but I know its possible on the older chips.

Cheers
 

erase lock bits 89c52

i am still wondering is it possible to break micros locks??? because the locks are in hardware and not in software...............


and if it possible then any well funded organisation(particularly govt organisation) will break the micro as needed..............



arnab/vu2bpw
 
8051 lock

arnab.bhaumik said:
i am still wondering is it possible to break micros locks??? because the locks are in hardware and not in software...............


and if it possible then any well funded organisation(particularly govt organisation) will break the micro as needed..............




dear bhaumik.. i also run a development firm in india. and may be we are nereby.
u still dont know much more abt lock bits i suppose. ur second last statement. make me stunned... really. bcs i am just nearby solving this problem.

Rony.
Click to expand...
 

how to read locked 8051?

hi rony.

what i mean to say is by giving instruction in software for lock bits we actually making some hardware changes in mcu...........they must implement locks in some circuitry in mcu..... please correct me if i am wrong.


i live in kolkata


arnab/vu2bpw
 

security lock bits of at89c52

Man you are crazy , the lock bit means security of code which is given by the manufacturer to the user . What else I can tell you
 

8051 lockbit break

hi manish,

for at89c52 user ther is three lock bits for the user LB1,LB2,LB3....... we program it or left unprogrammed.


my question is that we user just program the lock bits. but inside the at89c52 is ther a hardware circuitry that gets activated by the programmed lock bits or it just the lock bits.............


and if other than the circuitry, if the programming sequence just check the lock bits when it try to read the flash and refuses to read then its become the very easy to read the flash by some triky programmer/software.........

and all those thing i am just guessing. because you and i all dont know how the manufacturing company(atmal) implement the locks in ther 8051 mcu




arnab/vu2bpw
 

break 8051 forum

arnab.bhaumik said:
hi manish,

for at89c52 user ther is three lock bits for the user LB1,LB2,LB3....... we program it or left unprogrammed.


my question is that we user just program the lock bits. but inside the at89c52 is ther a hardware circuitry that gets activated by the programmed lock bits or it just the lock bits.............


and if other than the circuitry, if the programming sequence just check the lock bits when it try to read the flash and refuses to read then its become the very easy to read the flash by some triky programmer/software.........
=====================================================


dear bhaumik.

may be u and me dontknow as u have said; but people are there who know how atmel co. uses the lock bits.


now i am giving u two things to think. so u will not argue any more.

1> dont think the word "lock"as the conventional lock. its a phycological trap tht obstructs ppl to think more further ( same in ur case) ( the proof of this 1st clue u will find if u will think abt the second clue)

2> whn u erase the chip. wht do u think how how how-- the lock bits gets erased and how the program code gets ereased.

think about this two clues and i will get a clear-cut picture.

do write here.

-Rony.












and all those thing i am just guessing. because you and i all dont know how the manufacturing company(atmal) implement the locks in ther 8051 mcu




arnab/vu2bpw
Click to expand...
 

microcontroller programmer lock bit read

hi rony,

thanks for the reply, i will do a research about this in the net.


arnab/vu2bpw
 

89c52 fuse bit

arnab.bhaumik said:
hi rony,

thanks for the reply, i will do a research about this in the net.


arnab/vu2bpw
Click to expand...

friend,

let me know if u find domtthing more intresting in this area.

i am at gujarat.

--Rony.
 

at89c52 security lock bits

hi rony,

i searched the net and ther is a research paper from stanford university research paper, search the net for it and get it downloaded.

i am just not interested to break a mcu, just curious and thats why argued about it.


and if also 8051 and avr chips are breakeable i will prefer to observe the functionality and then program it by myself.........

arnab/vu2bpw
 

security bits of 89c52

hi,dear guy, have you finished ?

Added after 34 seconds:

hi,dear guy, have you finished ? devotion
 

unlock security bits of 89c52

yapp, we finished the topic, and the conclution is if u get the proper lab you can break a 8051.......................
hats off to the guy who did a phd about this subject at stanford university.............................................


arnab/vu2bpw
 

how to open lock bit mcs51

arnab.bhaumik said:
yapp, we finished the topic, and the conclution is if u get the proper lab you can break a 8051.......................
hats off to the guy who did a phd about this subject at stanford university.............................................


arnab/vu2bpw
Click to expand...

dear bhaumik.

i hv tht doccument.
various ways are shown there for different kinds of attacks on the different kinds controllers. but not a pertiquler method for 89c51,52.


any one has tried tht method for the .pdf attached above.? tel me the results if any one has.

please keep the subject live.. friends.


rony.
 

how unlock 8051

I found the source code and instructions. Here it is.
Remember this does not work on newer 8051.

I think it will work on older 87c51 or equivalent.
 
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