You're right, it should be: y = (T1 - ((ZCal * T2) / T2Cal)) / T2Cal, the division comes last. Sorry. Olin Lathrop wrote: >>y = (T1 - ((ZCal * T2) / T2Cal) / T2Cal > > > You've got a missing parenthesis in there somewhere. > -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu