Unisys Corporation

Sperry Corporation

George W Crozier

Bernard J McDevitt

A text orientation system for dot matrix printers includes a character adjust logic for orienting an image to be printed relative to a physical page. A first register in the character adjust logic receives a word of memory for either placement or character address. Each word has base bits and orientation bits. When the word is for address, the first register separates the base bits from the orientation bits and forwards the base bits to an adder and the orientation bits to an orientation adjust logic. Other bits of orientation adjust from a character processor are loaded into a second register and then to the orientation adjust logic for combining with orientation bits. A resulting adjusted signal goes to a Mux for selecting a displacement to produce a displacement signal. The displacement signal is then added to the previously separated base bits and forwarded as an adjusted character address to a character generator address. When the word is for placement, the first register also separates the base and orientation bits. The base bits are forwarded to a microprocessor in the character processor. The orientation bits are adjusted in the orientation adjust logic similar to the orientation bits of the address. The resulting adjusted signal also goes to the microprocessor in the character processor.

Text orientation system for dot matrix printers

Apparatus for shifting the output of a bit matrix character generator ninety degrees to provide ninety degrees shifted characters and comprises a barrel shifter for barrel shifting bit slices of the bit matrix characters coupled to a linear array shifter for linear array shifting the information that was first barrel shifted. A feedback loop which includes a rotate RAM memory having its output connected to the input of the barrel shifter means to twice barrel shift the information which was previously barrel shifted and then linear array shifted to provide a bit matrix character output which is rotated ninety degrees from the original bit matrix character provided at the output of the character generator.

Apparatus for high speed image rotation

A printing system incorporates a character generator having circuitry for the generation of proportional width printing. Further circuitry is utilized in conjunction with the foregoing circuitry to operate the system in a tabular mode for the columnar presentation of printed material. Two memories are employed. One memory stores data as to the components of characters which are to be printed, the data being stored in predesignated sets of addresses. Each of these components may be addressed by an address counter preset for counting through the set of addresses of a selected character. A tabbing or print signal is stored in the second memory to serve as position data in the tabbing mode. The second memory is addressed concurrently with a scanning of a print line whereby the stored data corresponds to a position on the print line. A comparator signifies the concurrence of a tab signal and the address counter of the first memory with the addressing of the print signal in the second memory, a compare designating the instant for initiating the printing of a further character. Thereby, most of the circuitry of the character generator can be utilized in both modes of the printing for reduced complexity and increased reliability.

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Hatfield, PA, United States of America

George W Crozier