code extraction from 89C55

[MITSUKO]

89c55 code

Hi everybody

Is there a way to extract the code out of a programmed , and most certainly , protected
89C55 . The chip is valuable , and i only have one , so i can't risk losing it .
Is there a safe way ??

 

[mm6349]

On 2001-10-05 08:42, MITSUKO wrote:
Hi everybody

Is there a way to extract the code out of a programmed , and most certainly , protected
89C55 . The chip is valuable , and i only have one , so i can't risk losing it .
Is there a safe way ??

I have similar problem that I have the equipment controlled by the Hitachi HD40L4818H which is a mask programmable microcontroller. How I can read the Rom inside the chip. I want to program another chip to replace the old one. Thanks.

 

[Trishool]

If you search elektroda you find more ,

BTW provide a long erase pulse with CE high and read one byte at a time ignore the byte and then reset then re read the whole code with CE low There is the protected code he he heeeee
PLEASE dont forget to read a byte before resetting, else you miss the code .This technique is applicable to 89CXX series only.

This clearly means you should do the following:--

1)PLEASE dont flood me with PM's :smile:

2)Read all the data sheet thoroughly.

3)Make yourself a SPECIAL programmer :wink: along with 74ls122 - 123 etc etc.

4)Then experement.

GOOD LUCK

 

[C-Man]

You can also check this out:
https://www.cl.cam.ac.uk/~sps32/mcu_lock.html

regards