Linuxcnc : an example communication with hdwr using custom Mcodes the receiver of this dats is an S32 and the shell emitted a float :( I fought for hours tryng to get the shell to emit integers then a user on the irc showed me the trick Thanks DG! contents of M110 file: #! /bin/sh halcmd sets onval ${1%%.*} halcmd sets offval ${2%%.*} contents of M112 file: #! /bin/sh halcmd sets ipkval ${1%%.*}