Line printer with recirculating line store and line print memories

Claim 2

A control for a printer having a plurality of print locations, each of which is successively presented with an ordered sequence of characters, one character at each location being selectable for simultaneous printing, comprising: means for receiving information in the form of binary coded characters in serial fashion corresponding to said presented characters, each coded character containing a pre-selected number of bits, one of said received coded characters representing a nonprinting control function; character storing means for storing at least one character, said receiving means upon receiving a first character transferring a second character to said character storing means, said character storing means including a line store memory for storing a plurality of characters corresponding to a full line of print at a plurality of line store character storage locations, and meaNs for providing an address for each of said line store storage locations, a line print memory for storing said plurality of characters in a plurality of line print character storage locations, and means for providing an address for each of said line print storage locations; means for comparing the presented characters with the stored characters; means for selecting a presented character at each location in accordance with said comparison; means for actuating said selecting means to initiate selection of said presented characters in response to reception of said control function character; and means for actuating said printer, after a character has been selected at each of said locations, to print all of said selected characters.

Claim 3

The printer control of claim 1 wherein said receiving means receives said bits in a serial fashion.

Claim 4

The printer control of claim 2 including means operably associated with said receiving means for providing an address for each character transferred to said character storing means.

Claim 5

The printer control of claim 3 wherein said address is a count representing the print location at which the character is to be selected.

Claim 6

The printer control of claim 3 including means operably associated with said receiving means for manually preselecting the address of the first character of each group of characters representing a line of print.

Claim 7

The printer control of claim 1 wherein said receiving means comprises a serial shift register.

Claim 8

The printer control of claim 1 wherein said received characters have a preselected bit parity and said control circuit includes means operatively associated with said receiving means for detecting an improper parity.

Claim 9

The printer control of claim 7 including means responsive to detection of an improper parity to store an error character in place of the character having the improper parity.

Claim 10

The printer control of claim 1 including means operably associated between said line print memory and said actuating means for actuating said selecting means to initiate selection of said presented characters in response to reception of a preselected number of characters corresponding to a full line of print.

Claim 11

The printer control of claim 1 including means operably associated between said receiving means and said character storing means for detecting an erroneous character and means responsive to said detector for transferring an error character to said character storing means in place of the erroneous character.

Claim 12

The printer control of claim 1 including means operably associated between said receiving means and said line store memory for transferring each character to a line store storage location having an address corresponding to the character address thereof.

Claim 13

The printer control of claim 1 wherein said line memory comprises a recirculating memory.

Claim 14

The printer control of claim 1 wherein the address providing means for said line print memory comprises the address providing means for said line store memory.

Claim 15

The printer control of claim 1 including means operably associated between said line store memory and said line print memory to transfer the characters from said line storage locations to the corresponding line print memory locations in response to the reception of a control character.

Claim 16

The printer control of claim 14 wherein said selecting means selects the presented character, at each print location corresponding to the address of the stored character that compares therewith.

Claim 17

The printer control of claim 1 wherein both said line storage memory and said line print memory comprise recirculating memories, both of said recirculating memories recirculating at the same rate.

Claim 18

In a printer having a plurality of type carrying members, each of said members carrying a plurality of type characters, drive means operatively connected to said members for moving each of said members to present successive characters on each member at respEctive aligned print locations, a character selector associated with each member actuatable for maintaining a selected type character on a member at its respective aligned print location, and printing means operatively associated with said members for simultaneously imprinting all of the presented type characters maintained at their respective print locations on a print receiving surface, a printing control system comprising: a character command receiver for receiving command input information in the form of coded command characters representative of the different characters on the type carrying members, one of said coded command characters representing a nonprinting control function for initiating a character type selection process; addressing means operatively associated with said receiver for providing each coded command character with an address representative of a print location; recirculatory storage means operatively associated with said addressing means including a line store memory having a plurality of line store memory positions each corresponding to an address for receiving and storing a plurality of command characters at their corresponding address corresponding to a full line of print, a line print memory having a plurality of line print memory positions each corresponding to an address for receiving the stored command characters from the line store memory and generating a line print command signal representative of the line of print desired to be printed, and means associated between said line store memory and line print memory to transfer the command characters from the line store memory positions to the line print memory positions in response to the reception of the command control character; a character detector associated with each type carrying member for sensing which character is at the corresponding print location and for generating a character detect signal representative thereof; comparator means operably associated between said character detector and said line print memory for comparing the line print command signal with each character detect signal, said comparator means generating a character select signal for said comparator means generating a character select signal for each type carrying member whenever said compared signals for that member match signifying that the desired type character on a given type carrying member is at the desired print location; a character selection actuator operably associated with each selector and said comparator means for actuating each selector in response to its corresponding character select signal and generating a print command signal when all of the selectors have been actuated; and a print actuator operably associated between said character selection actuator and said printing means for actuating said printing means in response to said print command signal whereby a line of type is imprinted on the print receiving surface.

Claim 19

In a printer having a plurality of type carrying members, each of said members carrying a plurality of type characters, drive means operatively connected to said members for moving each of said members to present successive characters on each member at respEctive aligned print locations, a character selector associated with each member actuatable for maintaining a selected type character on a member at its respective aligned print location, and printing means operatively associated with said members for simultaneously imprinting all of the presented type characters maintained at their respective print locations on a print receiving surface, a printing control system comprising: a character command receiver for receiving command input information in the form of coded command characters representative of the different characters on the type carrying members, one of said coded command characters representing a nonprinting control function for initiating a character type selection process; addressing means operatively associated with said receiver for providing each coded command character with an address representative of a print location; recirculatory storage means operatively associated with said addressing means including a line store memory having a plurality of line store memory positions each corresponding to an address for receiving and storing a plurality of command characters at their corresponding address corresponding to a full line of print, a line print memory having a plurality of line print memory positions each corresponding to an address for receiving the stored command characters from the line store memory and generating a line print command signal representative of the line of print desired to be printed, and means associated between said line store memory and line print memory to transfer the command characters from the line store memory positions to the line print memory positions in response to the reception of the command control character; a character detector associated with each type carrying member for sensing which character is at the corresponding print location and for generating a character detect signal representative thereof; comparator means operably associated between said character detector and said line print memory for comparing the line print command signal with each character detect signal, said comparator means generating a character select signal for said comparator means generating a character select signal for each type carrying member whenever said compared signals for that member match signifying that the desired type character on a given type carrying member is at the desired print location; a character selection actuator operably associated with each selector and said comparator means for actuating each selector in response to its corresponding character select signal and generating a print command signal when all of the selectors have been actuated; and a print actuator operably associated between said character selection actuator and said printing means for actuating said printing means in response to said print command signal whereby a line of type is imprinted on the print receiving surface.

Claim 20

The printing control system of claim 17 wherein said print actuator generates a print complete signal after a line of print has been imprinted, said system including means operatively associated with said print actuator and said selectors responsive to said print complete signal for releasing said selectors to their initial state.

Claim 21

The printing control system of claim 17 wherein said information comprises binary coded characters, each character containing a preselected number of bits, wherein said receiver receives said bits in serial fashion.

Claim 22

The printing control system of claim 19 wherein said receiver includes a serial shift register.

Claim 23

The printing control system of claim 19 wherein said characters have a preselected bit parity, said control system including means operatively associated with said receiver for detecting improper parity and means operatively associated with said detecting means and said storage means responsive to the detection of an improper parity to store an error character in place of the character having the improper parity.

Claim 24

The printing control system of claim 1 wherein said addressing means includes means operably associated with said storage means for manually preselecting the address of the first coded command character of each group of said characters with comprise a line of print.

Claim 25

The printing control system of claim 1 wherein said receiver receives a coded command character one at a time and transfers a second character to said storage means, said system including means operatively associated with said receiver for detecting an erroneous coded command character and means operatively associated with said detecting means and said storage means responsive to said erroneous character detector for transferring an error character to said storage means in place of the erroneous coded command character.

Claim 26

The printing control system of claim 17 wherein said line print command signal is generated after reception of a preselected number of coded command characters which correspond to a full line of print.

Claim 27

The printing control system of claim 17 wherein both said line store memory and said line print memory comprise recirculatory memories which recirculate at the same rate.

Claim 28

The printing control system of claim 17 wherein each type carrying member is a disc which carries the type characters in said ordered sequence on its outer peripheral surface, said type characters being presented for selection by rotation of said discs by said drive means, each selector stopping the rotation of its respective disc when the selected character thereon is presented at its print location, said character detector including a coded member mounted for rotation with each disc and means for detecting the code corresponding to the character being presented.