Video data display system

Claim 2

In a system for processing digital data alphanumeric signals comprising a television raster scanline display screen on which is to be displayed a row of alphanumerics, each alphanumeric corresponding to an alphanumeric code of said digital data signals, each alphanumeric to occupy an alphanumeric space in said row, each alphanumeric to be displayed on said screen by lighting selected dot spaces within said alphanumeric space on one or more of a plurality of scanlines within said row, the improvement comprising, in combination, A. A cathode ray tube; B. means for generating television type synchronizing signals; C. means to apply said synchronizing signals to said cathode ray tube to generate a television raster scanline pattern; D. input memory means for storing digital data alphanumeric signals in correspondence with said alphanumeric spaces; second memory means for receiving said digital data alphanumeric signals from said input memory means and comprising a circulating shift register having digital data stored in correspondence to said alphanumeric spaces; E. a read only memory (ROM) matrix responsive to a parallel stream of digital data signals identifying a character provided by said recirculating shift register and a vertical scanline signal representative of a scanline within said row for providing a parallel bit output signal representative of a sequence of dots comprising a line of that character on that scanline; F. means for counting raster scanlines which occur within said alphanumeric row to provide said vertical scanline signal; G. means responsive to said synchronizing signals to address said ROM with digital data in said second means for storing digital data to provide said parallel bit output signal; H. output storage means responsive to said parallel bit output signal for storing the latter signal; and I. means responsive to said synchronizing signals for serially reading out the stored bits in said output storage means to provide a serial bit stream of video pulses corresponding to dot spaces on said scanline for illumination to form the character portion represented and for applying said bit stream to said cathode ray tube to light said dot spaces.

Claim 3

Apparatus for displaying characters on a television raster scanline display screen comprising, first memory means for receiving digital data signals representative of characters to be displayed in the form of fields with each field consisting of a predetermined number of rows and each row consisting of a predetermined number of character spaces, second memory means comprising a recirculating character shift register memory for receiving a row of characters from said first memory means, memory field selector means for selecting a field of digital data for transfer row-by-row to said second memory means, television display means having a raster scan for displaying said characters of a selected field in said predetermined number of rows in respective ones of said predetermined number of character spaces, raster line counter means for providing a count signal representative of the line then being scanned on said television display means, permanent read only memory means responsive to digital input signals provided by said recirculating character shift register representative of said characters for providing decoded output signals identifying the form of the characters decoded thereby on the raster line then being scanned as a parallel bit output signal representative of a sequence of dots comprising a line of that character, synchronizing clock means for providing synchronizing signals to synchronize the flow of digital data from said first memory means to said character shift register and from the latter to said permanent read only memory with the display of said characters on said television display means, means for coupling said synchronizing signals to said first memory means, said character shift register means, said raster line counter means and said television display means for synchronizing said flow, video generator Means having output storage means for storing said parallel bit output signals, means responsive to said synchronizing signals for serially reading out the stored bits in said output storage means to provide a serial bit stream of video pulses corresponding to dot spaces on said scanline for illumination to form the character portion represented by the corresponding parallel bit output signal, and means for applying said video pulses to said television display means to illuminate said dot spaces thereon.

Claim 4

Apparatus for displaying characters on a television raster scanline display screen comprising, first memory means for receiving digital data signals representative of characters to be displayed in the form of fields with each field consisting of a predetermined number of rows and each row consisting of a predetermined number of character spaces, second memory means comprising a recirculating character shift register memory for receiving a row of characters from said first memory means, memory field selector means for selecting a field of digital data for transfer row-by-row to said second memory means, television display means having a raster scan for displaying said characters of a selected field in said predetermined number of rows in respective ones of said predetermined number of character spaces, raster line counter means for providing a count signal representative of the line then being scanned on said television display means, permanent read only memory means responsive to digital input signals provided by said recirculating character shift register representative of said characters for providing decoded output signals identifying the form of the characters decoded thereby on the raster line then being scanned as a parallel bit output signal representative of a sequence of dots comprising a line of that character, synchronizing clock means for providing synchronizing signals to synchronize the flow of digital data from said first memory means to said character shift register and from the latter to said permanent read only memory with the display of said characters on said television display means, means for coupling said synchronizing signals to said first memory means, said character shift register means, said raster line counter means and said television display means for synchronizing said flow, video generator Means having output storage means for storing said parallel bit output signals, means responsive to said synchronizing signals for serially reading out the stored bits in said output storage means to provide a serial bit stream of video pulses corresponding to dot spaces on said scanline for illumination to form the character portion represented by the corresponding parallel bit output signal, and means for applying said video pulses to said television display means to illuminate said dot spaces thereon.

Claim 5

Apparatus for displaying characters in accordance with claim 2 wherein said permanent read only memory comprises a matrix for converting parallel bit input signals for one scan line at a time for the lines of each of the characters in a row in sequence as it is simultaneously addressed in turn by each of the characters in said character shift register and by said count signal to provide said parallel bit output signal in which the presence of a dot is represented by one binary digit and the absence of a dot is represented by the other binary digit, and said output storage means comprises a plurality of flip-flops addressed in parallel and read out in series.