Digital raster timing encoder/decoder

• US 4,631,586 A
• Filed: 06/04/1984
• Issued: 12/23/1986
• Est. Priority Date: 06/04/1984
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Gennetten, Edward W., Gomez, Duane A.
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Parker, Michael D.
• Application Number:
  US06/617,220
• Time in Patent Office: 932 Days
• Field of Search: 358/141, 358/142, 358/145, 358/146, 358/147, 358/148, 358/150, 358/151, 360/42
• US Class Current: 348/495
• CPC Class Codes: H04N 5/06 Generation of synchronising signals
• CPC Class Codes: H04N 5/067 Arrangements or circuits at the transmitter end
• CPC Class Codes: H04N 7/56 Synchronising systems therefor

Abstract

The invention presents a digital raster timing encoder/decoder system when television raster synchronization pulses and other timing pulses and information data are generated. The invention comprises a digital clock source having coding circuitry which, combined with the clock source, encodes preselected digital signals containing information on raster synchronization control and timing, and also any other information data that is desired. The encoded signal output is transmitted either directly or via some special transmission link, for example by use of a Manchester Decoder clock multiplier (MDCM) system, to a receiving and decoding circuit. The received signal is decoded to create timing signals for operation control of the video television scanning system, and to read out other desired digital data that has been also transmitted within the signal. The system takes advantage of the fact that control signals of conventional synchronization pulses contain large deadband areas within which additional data information may be placed. Such additional digital information may be used to add other control pulse capability, or to add information transmission capability. A principal feature of the system is that only a single channel is needed to transmit synchronization pulses and any additional timing pulses or information of interest.

Claims

1. A digital raster timing encoder/decoder system, for generating horizontal and vertical control synchronization signals for a video raster scan and other preselected timing and digital data signals for said video scan, comprising:

a clock source;

an encoding means connected to receive a clock signal from the clock source, said encoding means being preprogrammed to encode preselected digital signals to be output by said encoding means; and

a decoding means disposed to receive the encoded digital signals which are output by said encoding means, said decoding means programmed to decode the digital signals;

wherein

the encoding means further comprises;

first means for counting connected to receive the clock source signal, said counting means disposed to accumulate count related to the time progression for horizontal video scan segments;

second means for counting connected to the output of the first counting means, said second counting means disposed to accumulate count in reference to the vertical control synchronization signals of the video raster scan;

first memory means connected to receive digital count signals from the first and second counting means;

second memory means connected to receive said digital count signals from the first and second counting means;

first means for registering, connected to receive said digital count signal from the second means for counting, a first digital timing signal from the first memory means, and also connected to receive the clock source signal, said first registering means storing said digital count signal for output; and

second means for registering connected to receive the stored digital count signal output from the first registering means, a second digital timing signal from the first memory means, said signal from the clock source, and a digital code signal from the second memory means, said second registering means encoding said code signal ahead of the digital count signal output from the first registering means, said second registering means outputting said encoded digital signals to said decoding means.

2. A digital raster timing encoder/decoder system according to claim 1 wherein the decoding means comprises:

a decoder register means connected to receive as an input the digital signals output from the second registering means of the encoding means, and also disposed to receive as a second input the clock source signal, wherein said decoder register means serially shifts out the digital input signals in a predetermined manner;

means for deciphering connected to receive as inputs the digital outputs from the decoder register means and from the second registering means of the encoding means, said deciphering means translating the input digital signals into output data and timing signals; and

means for converting the output translated signals into synchronization pulse waveforms wherein said synchronization pulse waveforms are output to control the operation of a video circuit.

3. A digital raster timing encoder/decoder system according to claim 2 wherein the converting means of the decoding means further comprises:

a plurality of jk flip-flop units prearranged to switch on and off according to the character of the translated signals from the deciphering means, said jk flip-flop units outputting conventional pulse waveform signals for control of a video raster scan.

4. A digital raster timing encoder/decoder system according to claim 3 which further comprises:

a Manchester Decoder Clock Multiplier (MDCM) system disposed between the encoding means and the decoding means, said MDCM receiving at its inputs the digital signals output from the encoding means, and also the clock source signal, said MDCM then outputting to the decoding means a conventional digital data signal and a base clock signal plus a multiplicity of clock signals with frequencies higher than, and including multiples of, the frequency of the base clock signal.

5. A digital raster timing encoder/decoder system according to claim 4 wherein the converting means of the decoding means comprises:

a plurality of said converting means connected to the output of the deciphering means, and each of the plurality of said converting means also connected to receive a separate signal of the MDCM output clock signals that are multiples of the base clock frequency, wherein the first of the converting means outputs a conventional synchronization pulse having a predetermined resolution, and wherein each of the plurality of the converting means outputs conventional synchronization pulse waveforms with n times the resolution of the first of the plurality of converting means, where n is a positive nonnegative integer.

6. A digital raster timing encoder/decoder system according to claim 5 wherein each converting means of the decoding means further comprises:

a plurality of jk flip-flop units with their inputs connected to receive the translated signals which are output from the deciphering means, and to receive preselected clocking signals from the MDCM system, wherein said flip-flop units are prearranged to switch on and off according to the character of their input signals, said jk flip-flop units outputting conventional pulse waveform signals for control of a video raster scan.

7. A digital raster timing encoder/decoder system according to claim 6 wherein the first and second memory means comprise:

read only memory devices.

8. A digital raster timing encoder/decoder system for generating horizontal and vertical control synchronization signals for a video raster scan system, and other preselected timing and digital data signals for said video scan, comprising:

a clock source;

an encoding means connected to receive a clock signal from the clock source, said encoding means being preprogrammed to encode preselected digital signals to be output by said encoding means; and

a decoding means disposed to receive the encoded digital signals which are output by said encoding means, said decoding means programmed to decode with digital signals;

wherein

the encoding means further comprises;

first means for counting, connected to receive the clock source signal, said counting means predisposed to accumulate count related to the time progression for horizontal video scan segments;

second means for counting, connected to the output of the first counting means, said second counting means disposed to accumulate count in reference to the vertical control synchronization signals of the video raster scan;

first memory means connected to receive digital count signals from the first and second counting means;

second memory means connected to receive said digital count signals from the first and second counting means;

means for generating a digital data signal;

first means for registering connected to receive said digital data signal from the generating means, a first coded digital timing signal from the first memory means, and also connected to receive the clock source signal, said first registering means storing said digital data signal, from the means for generating, for output;

second means for registering, connected to receive the stored signal output from the first registering means, said first digital timing signal from the first memory means, and also the signal from said clock source, said second registering means encoding a first digital signal comprising a logic 1 ahead of the stored signal output from the first registering means, said second registering means connected to output a first composite digital signal;

third means for registering, connected to receive and store for output the first composite digital signal output from the second registering means, a coded digital count signal from the second memory means, a second digital timing signal from the first memory means, and also connected to receive the clock source signal; and

fourth means for registering, connected to receive the stored signal output from the third registering means, said second digital timing signal from the first memory means, and also the clock source signal, said fourth registering means encoding a second digital signal, comprising a logic 1, ahead of the signal output from the third registering means, said fourth registering means outputting a second composite digital signal to said decoding means.

9. A digital raster timing encoder/decoder system according to claim 8 wherein the decoding means comprises:

a decoder register means connected to receive as an input the digital signal output from the fourth registering means of the encoding means, and also disposed to receive as a second input the clock source signal, wherein said decoder register means serially shifts out the digital input signal in a predetermined manner;

means for deciphering connected to receive as inputs the outputs from the decoder register means and from the fourth registering means of the encoding means, said deciphering means translating the input digital signals into input data and timing signals; and

means for converting the translated signals into source data and synchronization pulse waveforms wherein said synchronization pulse waveforms are output to control the operation of a video circuit.

10. A digital raster timing encoder/decoder system according to claim 9 wherein the converting means of the decoding means further comprises:

a plurality of jk flip-flop units with their inputs connected to receive the the translated signals from the deciphering means wherein said flip-flop units are prearranged to switch on and off according to the character of the translated sgnals, said jk flip-flop units outputting conventional pulse waveform signals for control of a video raster scan.

11. A digital raster timing encoder/decoder system according to claim 10 which further comprises:

a Manchester Decoder Clock Multiplier (MDCM) system predisposed between the encoding means and the decoding means, said MDCM receiving at its inputs the composite digital signal output from the encoding means, and also the clock source signal, said MDCM then outputting to the decoding means a conventional digital data signal and a base clock signal plus a multiplicity of clock signals with frequencies higher than, and including multiples of, the frequency of the base clock signal.

12. A digital raster timing encoder/decoder system according to claim 11 wherein the converting means of the decoding means comprises:

a plurality of said converting means connected to the output of the deciphering means, and each of the plurality of said converting means also connected to receive a separate signal of the MDCM output clock signals that are multiples of the base clock frequency, wherein the first of the converting means outputs a conventional synchronization pulse having a predetermined resolution, and wherein each of the plurality of the converting means outputs conventional synchronization pulse waveforms with n times the resolution of the first of the plurality of converting means, where n is a positive nonnegative integer.

13. A digital raster timing encoder/decoder system according to claim 12 wherein the first and second memory means comprise:

read only memory devices.

14. A digital raster timing encoder/decoder system according to claim 13 wherein the decoding means further comprises:

means connected to the output of the deciphering means for translating preselected portions of the input data and timing signals into a signal to be output and read by external monitoring equipment, said translating means also connected to directly receive the composite signal from the fourth registering means of the encoding means.

15. A digital raster timing encoder/decoder system according to claim 14 wherein the translating means comprises:

a mode gate; and

a data register, wherein the mode gate and data register strip off preselected input data and translate said data into a form that can be read out and monitored by external equipment.

16. A digital raster timing encoder/decoder system according to claim 15 wherein the first registering means further comprises:

an input from the second counting means whereby count data of vertical locations can be input as source data to be encoded by said first registering means.