I am currently doing some work interfacing with an embedded system. Within this system there are a series of hexadecimal configuration values, and a checksum at the end.
The four values are as follows:
The 'checksum' required is 047A0000
The very limited documentation I have for this suggests that the checksum is a byte addition of the four values, however I cannot replicate this.
How has this checksum been calculated, and can you work through it step-by-step?
It is the sum of all of the individual bytes taken one byte at a time.
>>> (0x0A + 0x34 + 0x61 + 0x49 +
0x0A + 0x34 + 0x61 + 0x69 +
0x0A + 0x34 + 0x60 + 0xC4 +
0x0A + 0x34 + 0x61 + 0x89)
1146
>>> 0x047a
1146
(It's possible that it's just a 16-bit checksum and the 0000 bytes are not a part of it. If they are, 047A0000 is an unusual byte arrangement for 0x47a—it's neither big nor little endian.)