Help with verification bits

Forum 2005-2010 (read only) Software Syntax & Programs
1

Hey gang

I have a video game console I am trying be able to modify the score on, I have found the eeprom which stores the score and managed to read it with my arduino it is a 32bit eeprom, I have found where the code is stored for example If the score where 112233 then the first 8bit's would be 33 then the next 8 22 then the next 8 11, then there is a 8 bit code which needs to match the score for it to work. I will post the code I have captured with the corresponding score below hopefully someone might be able to see how these last 8 bits are generated, I just cant see the pattern. All I have found out much by accident is that I can make it any combination of 2 or 4 eg{222444) and make the last 8 bits 10111011 and it will work. So this would make me think its not a crc type thing or else so many combination would not be able to have the same verification bits.

Here is some I have captured:

470347
4: 0100011100000011
5: 0100011110011001

470348
4: 0100011100000011
5: 0100011110011001

470353
4: 0101001100000011
5: 0100011110011001

470471
4: 0111000100000100
5: 0100011110101010

470481
4: 1000000100000100
5: 0100011110101100

470491
4: 1001000100000100
5: 0100011110101011

470503
4: 0000001100000101
5: 0100011110011011

Thanks in advance for anyone who may be able to help.

2

You say it's a 32 bit device, but mention only 16 and 8 bit values.

I have not the slightest clue what this:

470347
4: 0100011100000011
5: 0100011110011001

is supposed to refer to.

However, what I think you're asking is for our help to assist you cheating - would that be correct?

3

Hi

Not cheating I am trying to use the score board from a pinball machine,

470347
4: 0100011100000011
5: 0100011110011001

Now the top number is the score and the 32 bits after it contain the data in the eeprom , The first 8 bits expresses the last 2 numbers of the score as two separate 4 bit number. The next 8 bits is the middle two number and the next 8 bit contains the first 2 numbers. And the last 8 is the verification which I cant work out.

one more thing I sussed out is if the numbers making up the score only has 1 high bit aka (0100, 0001, 0010) then the last 8 bits will be 10111011

4

What does the "4:" and "5:" mean?

5

sorry just the address numbers that need to be used to address the eeprom, They can be ignored.