Relevant links: http://www.summitinstruments.com/knowledge_center/pdf/TN410.pdf http://www.lammertbies.nl/comm/info/crc-calculation.html?crc=1234567898765421&method=ascii

Adler32 is different from CRC32. It's much faster but a little bit less reliable. The free ZLIB.DLL from http://www.zlib.net/ has a function to calculate Adler32.