This is accomplished by using a standard PLC and the integrator's modular software to allow the proprietary system to communicate.
Companies in this article
Common Point Technologies Inc. (Sugar Grove, IL) is an automation systems integrator whose "Interposing PLC" allows packaging machines with proprietary controllers to communicate with other controllers, whether they're proprietary or industry-standard PLCs or PCs.
This is accomplished by using a standard PLC and the integrator's modular software to allow the proprietary system to communicate.