Question about the checksum.

[dviden]

The checksum is a simple and a way to verify that the buffer is written does not have errors.. with a certain degree of safety.
You add up all the values of the memory or the buffer that is lost as a byte, word (2 bytes), or long (4 bytes) and save..
in the case in which the write is not successful, it means that easily this sum is to be calculated will be differences from the right, and then you realize that at least one error is present
Note that is not a way to 100% because of errors there are two of them, hypothetically (because in practice the possibility that happening are very rare) the first may be cancelled by the second for the purposes of the calculation of the checksum.. (like if instead of writing 5 is written to 0.. and then after instead of writing 10, is written 15.. these 2 errors cancel out in the calculation of chksum).

Now if the files are identical and of the same machine, it seems to me impossible that the checksum is different.. in other words, if it means that there are differences, and then or the file is different, or it was written with one or more errors

since it seems that we understand checksum the families spoke to joseph are the calculation methods, which use the house ?
so I clarify the last doubt !!!

[MisterKappa]

The substance ? what I have said, in the sense that the sum in any way, all the memory and then you check it with the value that has to give..
Of course there can be many variants..
You add up all of the address byte, short or long, and then you can save it in a byte, short, long, or can you? to reserve a number of bits, such as to contain the woman as a whole (usually)..
Also not ? said that you need to add, you can use also other functions.
As you can see, variables (and there are many.. so not ? said to be implemented by different manufacturers in the same way

PS, we say that "understand" why? ? my job.. I have a degree in computer science and I work always

[dviden]

The substance ? what I have said, in the sense that the sum in any way, all the memory and then you check it with the value that has to give..
Of course there can be many variants..
You add up all of the address byte, short or long, and then you can save it in a byte, short, long, or can you? to reserve a number of bits, such as to contain the woman as a whole (usually)..
Also not ? said that you need to add, you can use also other functions.
As you can see, variables (and there are many.. so not ? said to be implemented by different manufacturers in the same way

PS, we say that "understand" why? ? my job.. I have a degree in computer science and I work always

we say that ? what I said explained a p? better the question was to understand because I was told that that was not so? what are "families" that are found in the mapping software, to the point I think I understand that the methods of calculation

[MisterKappa]

Of course, there are ways in which it is calculated

[cinqueturbo]

Sorry for the intrusion..
I think it's great to better understand the speech,
just this morning, or read and written to a panda 1,3 Mjet that already? I had to put in difficulty? with the flash!
vabb? and another story luckily or fixed.
the open with Titanium and I are the two drivers, changed only the checksum,
the file can be found: http://www.professionalchiptuning.ne...7&d=1366366938
or select the first or the intervention except to write it, and with sweat on the forehead and went all ok..
now I wonder what could happen? selezionavo the second?..

[Danny]

But written with that tool? On those ecu, however, MPPS at the check-in machine, and then to open the driver that I don't know if it could toppare the maps, then changes little. Otherwise if it is written with other programmers, I don't know in the slightest....

[cinqueturbo]

But written with that tool? On those ecu, however, MPPS at the check-in machine, and then to open the driver that I don't know if it could toppare the maps, then changes little. Otherwise if it is written with other programmers, I don't know in the slightest....

Danny to reason,
Mpps is all over him, but the BDM?
The Titanium corrects him when I save the File,
and there we are,
but if there are two drivers?
however, read and written with BDM..
nice discussion very important!!!!

[Danny]

BDM I don't know....Guys, I would you do a favor? behind c'? the file of Skoda .ori... Changed a single bit, and politely ripostate the file with the check correct? I want to be convinced of this...
To me, the ECM does not change the check...

[sportknight]

The bdm calculates it, also automatically, even for the marelli mjtd ? calculated automatically

[Danny]

Request....
Why? at all when you close the ECM will save the file with the check correct? Of course, opening up with the correct driver....To me it does not.
Another thing...Mpps, I by chance? to correct it, but how? Doing the procedure, he tells me to select the file you want to correct, select the ori, but then does nothing. Does not save any new files, and does not correct for either gi? this.