R
rjfjohnson
Hey,
I am trying to communicate with serial device and I need to know the
method used to calculate the 1digit checksum.
I have a commercial program that can communicate with the device, and a
serial port sniffer, and so I am able to get any number of sample
checksum digits. Below is a list of some.
I keep finding patterns, and it seems to revolve around the magic
number of 7.
If anyone could please help find this out, or does anyone know of a
brute-force method of determining a checksum?
Thanks,
Ryan Johnson.
1255 | 4
1265 | 7
1256 | 7
1355 | 5
3455 | 0
2455 | 1
1455 | 2
455 | 3
3355 | 7
2355 | 6
1355 | 5
355 | 4
255 | 5
1255 | 4
2255 | 7
3255 | 6
4255 | 1
425 | 4
1 | 6
2 | 5
3 | 4
4 | 3
5 | 2
6 | 1
7 | 0
8 | ?
9 | >
10 | 6
11 | 7
12 | 4
13 | 5
14 | 2
15 | 3
16 | 0
17 | 1
18 | >
19 | ?
21 | 4
23 | 6
2 | 5
22 | 7
222 | 5
3333 | 7
3 | 4
33 | 7
333 | 4
3333 | 7
123456789123456789 | 9
45 | 6
56 | 4
3567 | 0
3566 | 1
356 | 7
1234 | 3
123 | 7
I am trying to communicate with serial device and I need to know the
method used to calculate the 1digit checksum.
I have a commercial program that can communicate with the device, and a
serial port sniffer, and so I am able to get any number of sample
checksum digits. Below is a list of some.
I keep finding patterns, and it seems to revolve around the magic
number of 7.
If anyone could please help find this out, or does anyone know of a
brute-force method of determining a checksum?
Thanks,
Ryan Johnson.
1255 | 4
1265 | 7
1256 | 7
1355 | 5
3455 | 0
2455 | 1
1455 | 2
455 | 3
3355 | 7
2355 | 6
1355 | 5
355 | 4
255 | 5
1255 | 4
2255 | 7
3255 | 6
4255 | 1
425 | 4
1 | 6
2 | 5
3 | 4
4 | 3
5 | 2
6 | 1
7 | 0
8 | ?
9 | >
10 | 6
11 | 7
12 | 4
13 | 5
14 | 2
15 | 3
16 | 0
17 | 1
18 | >
19 | ?
21 | 4
23 | 6
2 | 5
22 | 7
222 | 5
3333 | 7
3 | 4
33 | 7
333 | 4
3333 | 7
123456789123456789 | 9
45 | 6
56 | 4
3567 | 0
3566 | 1
356 | 7
1234 | 3
123 | 7