HY-TEK Meet Manager CL2 and HY3 File Checksum Algorithms
I know this is old, hopefully someone hears this! I'm writing this Checksum generation code into an entry file parser I'm writing and I'm stuck on this lineanyone could shed any light on this for me I'd really appreciate it.
'We simple SUM the values here... For this string we get a checksum of 0x0B1E (done in HEX for clarity)'
I have summed the odd characters a few different ways and I never get '0x0B1E' as my result (yes, I'm converting the result to HEX). What exactly are we summing in each group? Integer values of the characters? Actual value of only the numbers? If
HY-TEK Meet Manager CL2 and HY3 File Checksum Algorithms --------------------------------------------------------
HY3 File Checksum:
We start with this line from an HY3 file:
E1M 8138AnackMB 200E 11 12 0S 4.00 4A 171.37Y 171.37Y
0.00 0.00 NN N 40
We take ONLY columns 1-129 since columns 130-131 contain the checksum
value:
E1M 8138AnackMB 200E 11 12 0S 4.00 4A 171.37Y 171.37Y
0.00 0.00 NN N |
We take and split the line into two different parts, part one is the
ODD numbered columns 1, 3, 5, 7... (I added the | to mark the end):
EM83AakB 20 11 0 40 4 113Y 7.7 00 00 N N |
We simple SUM the values here... For this string we get a checksum of
0x0B1E (done in HEX for clarity)
And part two has the EVEN numbered columns 2, 4, 6, ...:
1 18ncM 0E1 2 S .0 A 7.7 113Y .0 .0 N |
Here, we sum each of the values but multiply each by two before
summing... So we get a checksum of 0x15AC for thsi one.
Next we SUM both checksums:
0x0B1E + 0x15AC = 0x20CA
Then divide by 21 (decimal):
0x20CA -> 8394/21 = 399.71 but we just take the whole number part so
this is 399
Then add 205 to this result:
399 + 205 = 604
From this we take the last two digits backwards which is: 40 !!
-------------------------------------------------------------------------------------------------------------
CL2 File Checksum:
From a CL2 file we use a test line such as:
A01V3 02Meet Results Hy-Tek, Ltd WMM
3.0Cl Hy-Tek, Ltd
866-456-511112052009 MM40 N42
The checksum is contained in the last 4 columns (i.e. 157-160) and in
this case is " N42".
Here we calculate the checksum of the columns 1-156. For this example
we get 7861 or 0x1EB5.
Divide that result by 19 to get 413. Then add 211 to that result to
get 624.
Again we take the last two characters backward. In this case the
result is: 42.
The start of the checksum is either " N" or "NN" and this is
determined by the FIRST 2 CHARACTERs of the line. If the line
starts with "D0" we use "NN". Otherwise we use " N".
So this example line has a checksum value of " N42" according to this algorithm.
On Thursday, 28 October 2010 21:21:05 UTC+1, jwh wrote:
HY-TEK Meet Manager CL2 and HY3 File Checksum Algorithms --------------------------------------------------------
HY3 File Checksum:
We start with this line from an HY3 file:
E1M 8138AnackMB 200E 11 12 0S 4.00 4A 171.37Y 171.37Y
0.00 0.00 NN N 40
We take ONLY columns 1-129 since columns 130-131 contain the checksum value:
E1M 8138AnackMB 200E 11 12 0S 4.00 4A 171.37Y 171.37Y
0.00 0.00 NN N |
We take and split the line into two different parts, part one is the
ODD numbered columns 1, 3, 5, 7... (I added the | to mark the end): EM83AakB 20 11 0 40 4 113Y 7.7 00 00 N N |
We simple SUM the values here... For this string we get a checksum of 0x0B1E (done in HEX for clarity)
And part two has the EVEN numbered columns 2, 4, 6, ...:
1 18ncM 0E1 2 S .0 A 7.7 113Y .0 .0 N |
Here, we sum each of the values but multiply each by two before
summing... So we get a checksum of 0x15AC for thsi one.
Next we SUM both checksums:
0x0B1E + 0x15AC = 0x20CA
Then divide by 21 (decimal):
0x20CA -> 8394/21 = 399.71 but we just take the whole number part so
this is 399
Then add 205 to this result:
399 + 205 = 604
From this we take the last two digits backwards which is: 40 !!
-------------------------------------------------------------------------------------------------------------
CL2 File Checksum:
From a CL2 file we use a test line such as:
A01V3 02Meet Results Hy-Tek, Ltd WMM
3.0Cl Hy-Tek, Ltd
866-456-511112052009 MM40 N42
The checksum is contained in the last 4 columns (i.e. 157-160) and in
this case is " N42".
Here we calculate the checksum of the columns 1-156. For this example
we get 7861 or 0x1EB5.
Divide that result by 19 to get 413. Then add 211 to that result to
get 624.
Again we take the last two characters backward. In this case the
result is: 42.
The start of the checksum is either " N" or "NN" and this is
determined by the FIRST 2 CHARACTERs of the line. If the line
starts with "D0" we use "NN". Otherwise we use " N".
So this example line has a checksum value of " N42" according to this algorithm.
Just want to add my thanks for your time and effort on this. It's a huge time-saver.
HY-TEK Meet Manager CL2 and HY3 File Checksum Algorithms --------------------------------------------------------
HY3 File Checksum:
We start with this line from an HY3 file:
E1M 8138AnackMB 200E 11 12 0S 4.00 4A 171.37Y 171.37Y
0.00 0.00 NN N 40
We take ONLY columns 1-129 since columns 130-131 contain the checksum
value:
E1M 8138AnackMB 200E 11 12 0S 4.00 4A 171.37Y 171.37Y
0.00 0.00 NN N |
We take and split the line into two different parts, part one is the
ODD numbered columns 1, 3, 5, 7... (I added the | to mark the end):
EM83AakB 20 11 0 40 4 113Y 7.7 00 00 N N |
We simple SUM the values here... For this string we get a checksum of
0x0B1E (done in HEX for clarity)
And part two has the EVEN numbered columns 2, 4, 6, ...:
1 18ncM 0E1 2 S .0 A 7.7 113Y .0 .0 N |
Here, we sum each of the values but multiply each by two before
summing... So we get a checksum of 0x15AC for thsi one.
Next we SUM both checksums:
0x0B1E + 0x15AC = 0x20CA
Then divide by 21 (decimal):
0x20CA -> 8394/21 = 399.71 but we just take the whole number part so
this is 399
Then add 205 to this result:
399 + 205 = 604
From this we take the last two digits backwards which is: 40 !!
-------------------------------------------------------------------------------------------------------------
CL2 File Checksum:
From a CL2 file we use a test line such as:
A01V3 02Meet Results Hy-Tek, Ltd WMM
3.0Cl Hy-Tek, Ltd
866-456-511112052009 MM40 N42
The checksum is contained in the last 4 columns (i.e. 157-160) and in
this case is " N42".
Here we calculate the checksum of the columns 1-156. For this example
we get 7861 or 0x1EB5.
Divide that result by 19 to get 413. Then add 211 to that result to
get 624.
Again we take the last two characters backward. In this case the
result is: 42.
The start of the checksum is either " N" or "NN" and this is
determined by the FIRST 2 CHARACTERs of the line. If the line
starts with "D0" we use "NN". Otherwise we use " N".
So this example line has a checksum value of " N42" according to this algorithm.
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