Buffered peripheral-controller

Digital interface unit 1 for activating a peripheral module, in particular for activating a solenoid valve for an injection system, having an output register 2 to 5 which outputs and holds a control data value when activated by a control signal 18, MST_E, there being connected upstream of the output register a buffer register 12 to 15, 24 to 27 which temporarily stores the control value to be outputted, prior to transfer to the output register, in order to make possible a precisely simultaneous output of control values via a plurality of output registers 2 to 5 when the control values are supplied sequentially from a microprocessor system (6, Fig.2).