Post by thread:[PIC]: Checksum of a hexfile

How is the checksum of a pic hexfile calculated? ie: :020670001A2945 in this line 0x45 is CS, but i don't know why. regards, Ben -------------------------- Benjamin Menküc Auto-Intern GmbH Haberlandstr. 125 44359 Dortmund Tel: 0231-1893070 Fax: 0231-93699548 http://www.auto-intern.com Meinen PGP-Schlüssel kann man unter: http://www.auto-intern.com/php/pgp_menkuec.php finden. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email spam_OUTlistservTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

Ben, To calculate the checksum, add all of the data bytes (exclude the : and the checksum) 02 + 06 + 70 + 00 + 1A + 29 = BB keep the low order byte (still BB) take the twos complement (not BB + 1 = 44 + 1 = 45) To use the checksum to check the result, add all the data bytes including the checksum 02 + 06 + 70 + 00 + 1A + 29 + 45 = 100 The low byte should be (and is) 00. Note that the Intel hex file format (like this) uses twos complement for the checksum, while Motorola S-record format uses ones complement. Quoting Benjamin Menk|c <.....benjaminKILLspam@spam@AUTO-INTERN.COM>: {Quote hidden}> How is the checksum of a pic hexfile calculated? > > ie: > :020670001A2945 > > in this line 0x45 is CS, but i don't know why. > > > > regards, > > > > Ben > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listservKILLspammitvma.mit.edu with SET PICList DIGEST in the body