CHECKSUM CHALLENGE - (US$ 100)
From: Carlos Gomez (carlos_gomez_73_at_hotmail.com)
Date: 11 Feb 2004 08:45:36 -0800
We're offering US$100 to have a checksum/CRC algorithm
We have a microcontroller-based system that connects via modem to a
remote PC. The PC runs a software that talks to the microcontroller,
sending and receiving data. The person that developed this system for
us is no longer available.
We have the protocol to control the system but we don't know the
checksum algorithm and therefore can't get the new data accepted by
the receiving machine.
Apparently the last two bytes of each data packet are Checksum/CRC.
The first byte is the number of bytes that follows in the packet (we
don't know if this byte is computed in the Checksum/CRC).
Examples of the data and resultant checksum are provided below.
If interested, please email me for further details. I will let you
know how many others have applied. The money goes to the first one who
returns a working algorithm preferably implemented in VB.
06 FF 01 FF 09 FF 46 FF 36 FF D8 FF F5
06 FF 01 FF 09 FF 0A FF 3C FF F1 FF 95
06 FF 01 FF 09 FF 7C FF 2A FF E0 FF A3
06 FF 01 FF 09 FF A6 FF 36 FF D8 FF C1
06 FF 01 FF 09 FF D6 FF 2A FF DE FF 5B
06 FF 01 FF 07 FF 06 FF 1E FF 7D FF D7
06 FF 01 FF 07 FF 24 FF F5 FF 23 FF 91
06 FF 01 FF 08 FF 80 FF 1E FF 22 FF 9D
06 FF 01 FF 08 FF 9E FF 42 FF 72 FF C1