A packaging machine under control of an electronic control system is set forth. The packaging machine includes a plurality of servo driven packaging stations that execute the processes required to fill and seal a carton. Each of the packaging stations is driven by one or more servomotors associated therewith. A plurality of servo amplifiers are connected to the servomotors to control the rotational movement of the servomotors thereby to effect control of the motion of the various components associated with each if the packaging stations. The packaging machine further includes at least two programmable devices connected for communication over a common bus. A programmable axis manager (PAM) is connected to control the plurality of servo amplifiers and, thus, the motion profiles of the servomotors and components of the respective processing station. A programmable logic controller (PLC) is connected to receive and transmit input/output signals associated with the plurality of packaging stations. The PAM and the PLC communicate data variable values over the common bus using predetermined fingerprints assigned to each variable value. Use of the fingerprint/variable value protocol allows high speed communication between the PLC and PAM thereby allowing the PLC and PAM to be viewed as a single control unit.
