Peripherals interrupt control unit

Claim 1

A peripheral interrupt control unit for selectively providing interrupt signals from a plurality of peripheral units to a central processing unit of the type capable of executing a program stored in a memory, said interrupt signals being sent to said central processing unit in an order determined by the priority of the peripheral unit requesting an interrupt, said interrupt control unit comprising: an interrupt register having a plurality of cells, ecah of said cells storing an associated interrupt request signal generated by one of said peripheral units; means for storing in said cells said interrupt request signals; a single priority decoder connected with the output of said interrupt register for selecting one of said interrupt request signals according to a predetermined priority order to be transmitted to said central processing unit and for generating a code combination of signals associated with said selected interrupt request signal; means for transmitting said code combination of signals to said central processing unit; and clearing means connected between the output of said priority decoder means and said interrupt register and enabled by an end signal generated by said central processing unit, said clearing means including a decoder means responsive to said generated code combination for clearing the cell storing the interrupt request signal selected by said decoder means of said clearing means.