In a programmable controller of the type including a microprocessor having output address terminals, output address lines extending to external addressable devices, input/output bi-directional data terminals and means for applying a binary status code made up of binary signals on the data terminals at a preselected time during a cycle of the microprocessor and indicative of the type of machine cycle to be processed by the microprocessor there is provided a system for energizing a hardwired logic circuit in response to a status code and logic on said address lines.