CIRCUIT ARRANGEMENT FOR ENTERING CONTROL COMMANDS INTO A MICROCOMPUTER SYSTEM

摘要

With this circuit arrangement a plurality of control commands can be inputted into a microcomputer system by means of only a single input channel and the microprocessor is relieved of the operation of scanning the peripherals for detecting the presence of control commands. By means of a release or enabling signal the microprocessor signals its preparedness for receiving interruptions, and the release or enabling signal activates a scanning and comparator unit arranged between an interrupt requirement input of the microprocessor and a peripheral unit. Thereafter the scanning and comparator unit scans control command transmitters grouped together in the peripheral unit and characterized by an address and compares the switching state thereof with a switching state which is stored under the same address. If the two switching states are different, there is generated an interrupt requirement or requisition and the stored switching state is adapted to the switching state of the control command transmitter.