Intelligent programmable process control system

An intelligent programmable process control system for controlling a process, said system comprising:

• (a) at least one analog-to-digital converter means for generating a digital output corresponding to an analog voltage input signal from an analog sensor device located along said process;
• (b) at least one digital-to-analog converter means for generating an analog voltage output signal corresponding to a digital input to control a controllable analog device located along said process;
• (c) digital processor means coupled to the digital output of said analog-to-digital converter means and coupled to provide the digital input to said digital-to-analog converter means, said digital processor means controlling at least one analog loop control function of said process via said analog-to-digital converter means and said digital-to-analog converter means;
• (d) boolean processor means for scanning and executing a sequence of boolean logic functions;
• (e) image register means for storing input bits representative of the on/of states of sensors located along said process and output bits representative of the on/off states of controllable devices located along said process, said boolean processor means being coupled to said image register means for executing said sequence of boolean logic functions in accordance with the states of said input bits to generate said output bits;
• (f) selectively addressable memory means;
• and communication means including a direct path and a path through selectable addresses of said selectively addressable memory means coupling said digital processor means to said boolean processor means to communicate instructions and data between said digital processor means and said boolean means, said digital processor means and said boolean processor means normally operating independently and asynchronously with respect to each other.