Option protocol arrangement for stored program rectifier controller

A power plant control system including:

• a master control means for monitoring the status of a power plant system comprising:
• a master processing unit including first associated memory means under control of the master processing unit,
• an option control means comprising:
• an option processing unit including second associated memory means under control of the option processing unit and additional memory means in location with the option processing unit,
• the control system including connection means for selectively coupling the additional memory means to the master processing unit,
• the master control means further including:
• means for polling the option processing unit in response to an interrupt signal generated by an option processing unit,
• means associated with the option processing unit for generating a word indicative of having initiated an interrupt and storing the word at a predetermined location,
• means associated with the master processing unit for accessing the predetermined location and evaluating the word, and
• means for having the master processing unit execute a stored program included in the additional memory means.

A method for enabling a master controller of a power plant to respond to selected ones of a plurality of options comprising:

• the steps of;
• generating an interrupt signal in response to an option command and coupling it to the master controller,
• locating a stored program associated with each option at a common address in an address field of the master controller,
• executing the stored program associated with an active option by executing stored instructions at the common address of the active option.