Printer control logic

Control means for a printer having a matrix print head which moves across a record medium, said print head printing information on said medium by selective operation of the print elements of said print head, said control means comprising;

• means for providing position signals at periodic interim positions as said print head moves across said medium;
• interruptable processor means responsive to said position signals for being interrupted to provide a control signal to selectively operate said print elements after being interrupted;
• wherein said position signal providing means includes printer emitter means for providing a signal which changes in response to specific interval movement of said print head;
• wherein said position signal providing means further includes means responsive to said emitter means signal for providing an interrupt signal to said processor means each time said emitter means signal changes;
• wherein said means for providing said interrupt signal further responds to a second control signal from said processor means;
• and
• wherein said means for providing said interrupt signal includes exclusive OR means responsive to said emitter means signal and to said second control signal, said interrupt signal being provided by said exclusive OR means whenever said emitter means signal changes, said processor means further responding to said interrupt signal to cause a corresponding change in said second control signal so that subsequent interrupt signals are provided by said exclusive OR means upon subsequent emitter means signal changes.

In a wire matrix printer having a print head which moves bidirectionally across a record medium, said print head including a plurality of actuatable print wires which can be actuated as said print head moves across said medium, each wire, upon actuation, striking ribbon means against said medium, whereby a mask is printed on said medium, said wire matrix printer further having printer emitter means across which said print head moves for providing a a sequence of signals manifesting each successive incremental movement of said print head, said printer emitter signal sequence being different for different directions that said printer moves, said wire matrix printer further having an improvement of control means comprising:

• programmable processor means having an interrupt input, and
• decoding logic means responsive to said printer emitter signals and to enabling signals provided by said processor means for providing an interrupt signal to said interrupt input each time an incremental movement of said print head is manifested by said emitter signals;
• said processor means being programmed in response to said decoding logic means signal being applied to said interrupt input thereof to provide actuation signals causing the selective actuation of said wires, said actuation signals being provided a desired time after the provision of said decoding logic means signals, said processor means further providing said enabling signals to said decoding logic means in accordance with the then occurring printer emitter signal sequence.

In a wire matrix printer having a print head which moves across a record medium, said print head including a plurality of actuatable print wires which can be actuated as said print head moves across said medium, each wire, upon actuation, striking ribbon means against said medium, whereby a mark is printed on said medium, said wire matrix printer further having printer emitter means across which said print head moves for providing a signal manifesting each successive incremental movement of said print head, said wire matrix printer further having an improvement of control means comprising;

• programmable processor means having an interrupt input, and
• decoding logic means responsive to said printer emitter signals for providing a signal to said interrupt input each time an incremental movement of said print head is manifested by said emitter signals;
• said processor means being programmed in response to said decoding logic means signal being applied to said interrupt input thereof to provide actuation signals causing the selective actuation of said wires, said actuation signals being provided a desired time after the provision of said decoding logic means signal;
• wherein said control means further comprises means for measuring said desired time;
• wherein said means for measuring said desired time includes a programmable timer which is programmed to provide a signal to a second interrupt input of said processor means said desired time after being programmed;
• wherein said programmable timer is programmed by said processor means to provide a signal to said second interrupt input at a plurality of times following said decoding logic means signal being applied to said first mentioned interrupt input;
• wherein said decoding means logic further responds to a control signal provided by said processor means, said control signal having a state related to the value of said print emitter signals after said decoding means logic signal is applied to said interrupt input;
• and
• wherein said decoding means logic includes exclusive OR means responsive to said print emitter means signal and to said control signal;
• said first interrupt signal being provided by said exclusive OR means whenever said print emitter means signal manifests an incremental movement of said print head, said processor means responding to said first interrupt signal to cause a change in said control signal so that subsequent interrupt signals are provided by said exclusive OR means for subsequent print emitter means signals.

Control means for a printer having a matrix print head which moves across a record medium, said print head printing information on said medium by selective operation of the print elements of said print head, said control means comprising:

• means for providing positioning signals at periodic interim positions as said print head moves across said medium;
• programmable timer means which provides a signal after the expiration of a time programmed therein;
• and
• processor means responsive to said positioning signals for programming said timer means to provide signals after a given time to selectively cause the operation of said print elements, said timer means signal being coupled to interrupt said processor means, said processor means providing signals to cause said print elements to be operated in response to said timer means signal.

In a wire matrix printer having a print head which moves across a record medium, said print head including a plurality of actuatable print wires which can be actuated as said print head moves across said medium, each wire, upon actuation, striking ribbon means against said medium, whereby a mark is printed on said medium, said wire matrix printer further having printer emitter means across which said print head moves for providing a signal manifesting each successive incremental movement of said print head, said wire matrix printer further having an improvement of control means comprising:

• programmable processor means having an interrupt input;
• and
• programmable timer means responsive to programming signals provided thereto from said processor means for being set to provide an interrupt signal to said interrupt input a desired time after being programmed;
• said processor means being programmed to provide actuation signals in response to said interrupt signal, said actuation signals causing the selective actuation of said wires.