ift ▁rout ▁tool ▁up ▁▁ ▁M 3 0 ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁ ▁End ▁of ▁file ▁ ▁Ex cell on ▁format ▁ ▁The ▁name ▁Ex cell on ▁format ▁is ▁derived ▁from ▁the ▁company ▁Ex cell on ▁Autom ation ▁( not ▁to ▁be ▁confused ▁with ▁Ex cell on ▁Software ), ▁which ▁was ▁the ▁market ▁leader ▁in ▁PC B ▁dr illing ▁and ▁routing ▁machines ▁during ▁the ▁ 1 9 8 0 s , ▁and ▁whose ▁propriet ary ▁format ▁became ▁widely ▁used . ▁ ▁There ▁are ▁actually ▁two ▁Ex cell on ▁formats , ▁the ▁older ▁Ex cell on ▁ 1 ▁and ▁Ex cell on ▁ 2 . ▁Ex cell on ▁ 2 ▁is ▁a ▁su pers et ▁of ▁IP C - NC - 3 4 9 . ▁Comm ands ▁from ▁both ▁are ▁sometimes ▁confusing ly ▁mixed ▁in ▁the ▁same ▁file . ▁ ▁Ex cell on ▁Autom ation ▁stopped ▁publishing ▁the ▁specification ▁of ▁its ▁format , ▁without ▁statement ▁on ▁the ▁IP ▁and ▁usage ▁rights ▁of ▁the ▁format . ▁An ▁arch ived ▁copy ▁exists . ▁ ▁The ▁specification ▁is ▁ambigu ous , ▁leading ▁to ▁different ▁interpret ations , ▁especially ▁in ▁the ▁area ▁of ▁coordinates ▁and ▁units . ▁It ▁is ▁target ed ▁at ▁input ▁for ▁dr ill / rout ▁machines , ▁not ▁C AD ▁to ▁C AM ▁data ▁exchange . ▁ ▁Ind ef in ite ▁NC ▁files ▁ ▁For ▁C AD / C AM ▁data ▁exchange ▁often ▁NC ▁files ▁are ▁used ▁that ▁only ▁that ▁only ▁v agu ely ▁follow ▁any ▁specification . ▁These ▁files ▁contain ▁a ▁few ▁IP C - NC - 3