Long description

The figure consists of two blocks labeled C P U and an Interrupt controller connected from their bottom to a bus. The interrupt controller block contains three sub-blocks. A disk, keyboard, clock, and printer are pointed to the interrupt controller block. The disk is connected to the interrupt controller block using an arrow labeled 1, and the device is finished. An arrow labeled controller issues interrupt points from the interrupt controller block to the C P U block. Another arrow labeled 3, C P U acks interrupt points from the C P U block to interrupt the controller block.