There is disclosed herein printer control logic for controlling a matrix printer. The control logic includes an interruptable microprocessor, together with associated memory. Additionally the control logic includes a programmable timer which provides a signal a determined time after being programmed. The control logic responds to print emitter signals manifesting an incremental movement of the print head by interrupting the microprocessor. The microprocessor then programs the timer to provide signals after a programmed delay time to again interrupt the microprocessor. The microprocessor then provides signals causing the operation of the print elements on print head.