Self-diagnosis arrangement for a video display and method of implementing the same

Abstract

A self-diagnostic arrangement for a video display apparatus and method effectuating the same is disclosed. The apparatus according to the present invention includes a cable connector, amplifiers and a cathode ray tube and comprises a microprocessor storing information on a display status, for selectively switching signals to generate horizontal and vertical sync signals for displaying a variety of self-diagnostic displays, an on screen display IC for supplying a blanking signal and a video signal correspondingly responsive to information supplied from the microprocessor and a H/V deflection circuit for supplying on screen display video. signals to the CRT. There is also provided a method of self-diagnosis, which comprises the steps of generating internal horizontal and vertical sync.signals sync signals of predetermined frequency levels and displaying self-diagnostic screens representing video component colors and a display status.

What is claimed is:  
     
       1. A video display apparatus including a microprocessor, on-screen display integrated circuit and a cathode ray tube, characterized in that: 
       the microprocessor receives horizontal and vertical synchronization frequencies, generates internal horizontal and vertical synchronization frequencies and determines a state of connection between said apparatus and an external system; and  
       the cathode ray tube is fed with either one of said horizontal and vertical synchronization frequencies or said internal horizontal and vertical synchronization frequencies determined by said microprocessor in response to the state of connection.  
     
     
       2. A method for self-diagnosis testing of a video display apparatus including a cable connector, a microprocessor, on-screen display means and a cathode ray tube, said method comprising the steps of: 
       checking said cable connector to determine connection to an external system;  
       generating horizontal and vertical synchronizing frequencies in said microprocessor in case of no connection between said cable connector and external system; and  
       outputting a self-diagnosis display signal to said cathode ray tube from said on-screen display means responsive to an input signal supplied from said microprocessor.  
     
     
       3. The method of  claim 2 , further comprising the steps of: 
       detecting an input signal from a key pad; and  
       displaying a pre-stored self-diagnostic display on a screen of said cathode ray tube in response to said input signal from said key pad.  
     
     
       4. A method for self-diagnosis of a video display apparatus including a cable connector to which a signal cable of an external system is engagedly connected, amplifier means for amplifying a video signal input via said cable connector and a cathode ray tube for displaying said amplified video signal input from said amplifier means, said method comprising the steps of: 
       a first process for generating internally generated horizontal and vertical synchronizing signals of predetermined frequencies, respectively, on an occasion of no connection between said signal cable and cable connector; and  
       a second process for generating signals for at least two self-diagnosis display screens representing a detail of video component colors and display status from predetermined data stored in said apparatus.  
     
     
       5. A video display apparatus including a cable connector to which a signal cable of an external system is engagedly connected, an amplifier for receiving a first video signal supplied via said cable connector and a cathode ray tube for displaying said signal input from said amplifier, said apparatus comprising: 
       a microprocessor storing information for an image status being displayed, for selectively switching between internal horizontal and vertical synchronizing signals from an internal generator and external horizontal and vertical synchronizing signals from said external system to provide output horizontal and vertical synchronizing signals having predetermined frequency levels based on a connection status between said signal cable and said cable connector;  
       means for supplying a plurality of second video signals corresponding to said stored information provided by said microprocessor to said amplifier; and  
       horizontal and vertical deflection circuits, responsive to said output horizontal and vertical synchronizing signals input from said microprocessor, for supplying horizontal and vertical deflection signals to said cathode ray tube.  
     
     
       6. The video display apparatus of  claim 5 , wherein said microprocessor further comprises: 
       oscillator means for generating an oscillation clock frequency;  
       horizontal and vertical synchronizing circuits as said internal generator for generating said internal horizontal and vertical synchronizing signals using said oscillation clock frequency; and  
       a pair of switches for selectively switching between said internal horizontal and vertical synchronizing signals and said external horizontal and vertical synchronizing signals.  
     
     
       7. The video display apparatus of  claim 5 , wherein said predetermined frequency levels are adjustable. 
     
     
       8. The video display apparatus of  claim 6 ,wherein said predetermined frequency levels are adjustable. 
     
     
       9. A video display apparatus, comprising: 
       
         a signal cable;  
       
       
         a cable connector for connecting the video display apparatus to an external system;  
       
         a microprocessor stage having key input ports, a horizontal input terminal and a vertical input terminal respectively disposed to receive an external horizontal synchronizing signal and an external vertical synchronizing signal from said external system via said signal cable, said microprocessor comprising a generator generating an internal horizontal synchronizing signal and an internal vertical synchronizing signal and selectively outputting one of said external horizontal synchronizing signal and said internal horizontal synchronizing signal and one of said external vertical synchronizing signal and said internal vertical synchronizing signal, said microprocessor stage storing self - diagnostic video information;    
       
         a horizontal and vertical deflection stage generating horizontal and vertical flyback signals in response to the horizontal and vertical synchronizing signals output by said microprocessor stage;  
       
         a video device generating an on - screen display comprising color components and a blanking signal corresponding to said self - diagnostic video information and said horizontal and vertical flyback signals for generating an on screen display video signal comprising color components and a blanking signal;    
       
         a preamplifier outputting an amplified signal corresponding to an external video signal received from said cable connector and said on screen display video signal; and  
       
         a video amplifier driving said video device to provide said on - screen display by amplifying said amplified video signal.   
     
     
       10. A video display apparatus, comprising: 
       
         a video device providing displays of variable video images;  
       
       
         a circuit driving said video device to provide said displays; and  
       
       
         a microprocessor based controller monitoring reception of external horizontal and vertical synchronization frequencies, generating internal horizontal and vertical synchronization frequencies and determining a state of signal connection between said video device and an external system supplying video signals and selectively applying to said circuit one of said external horizontal and vertical synchronization frequencies and said internal horizontal and vertical synchronization frequencies to control said displays as determined by said controller in dependence upon said state of connection between said video device and said external system. 
       
     
     
       11. A method of generating a self- diagnostics video display, comprising the steps of:    
         checking a cable connector of a video display apparatus including a cable connector, a microprocessor, on - screen display circuit and a display means to determine connection to an external system;    
       
         generating horizontal and vertical synchronizing frequencies in said microprocessor when no connection is detected between said cable connector and external system; and  
       
         outputting a self - diagnosis display signal to said display means from said on - screen display circuit responsive to an input signal supplied from said microprocessor.   
     
     
       12. The method of  claim 11 , further comprising the steps of: 
       
         detecting an input signal from a key pad; and  
       
         displaying a pre - stored self - diagnostic display on said display means in response to said input signal from said key pad.   
     
     
       13. The method of  claim 11 , further comprised of the step of monitoring said connection by detecting external horizontal and vertical synchronization frequencies from said external system. 
     
     
       14. The method of  claim 11 , further comprised of the step of monitoring said connection by detecting a logic state of a reference signal from said external system. 
     
     
       15. The method of  claim 11 , further comprised of the step of generating a key signal output in response to a second diagnosis display signal. 
     
     
       16. The method of  claim 11 , further comprised of the step of applying a message signal to said display means so as to inform user of a state of said connection. 
     
     
       17. A method of generating a self- diagnostics video display, comprising:    
       
         making a determination of whether a signal cable of a video device providing displays of variable video images is connected to a cable connector supplying a video signal;  
       
       
         generating internal horizontal and vertical synchronizing signals when said determination indicates that said signal cable is not connected to a cable connector supplying a video signal;  
       
         displaying an initial menu of a plurality of self - diagnostic functions;    
         soliciting an input by key - stroke manipulation via a video display on said video device; and    
         responding to said key - stroke by displaying on said video device a detail of self - diagnostic information corresponding to said key - stroke.   
     
     
       18. A method for self- diagnosis testing of a video display apparatus including a cable connector to which a signal cable of an external system is engagedly connected, a circuit controlling a video signal input via said cable connector and a display means for displaying said video signal input from said circuit, said method comprising the steps of:    
       
         generating internally generated horizontal and vertical synchronizing signals of predetermined frequencies, respectively, when there is no connection between said signal cable and cable connector; and  
       
         generating signals for at least two self - diagnostic displays representing a detail of video component colors and a display status from predetermined data stored in said apparatus.   
     
     
       19. The video display apparatus of  claim 18 , wherein said microprocessor further comprises: 
       
         oscillator means for generating an oscillation clock frequency;  
       
       
         horizontal and vertical synchronizing circuits as said internal generator for generating said internal horizontal and vertical synchronizing signals using said oscillation clock frequency; and  
       
       
         a pair of switches for selectively switching between said internal horizontal and vertical synchronizing signals and said external horizontal and vertical synchronizing signals. 
       
     
     
       20. The video display apparatus of  claim 18 , wherein said predetermined frequency levels are adjustable. 
     
     
       21. A video display apparatus, comprising: 
       
         a cable connector disposed to be functionally connected to a signal cable of an external system supplying a first video signal;  
       
       
         an amplifier receiving said first video signal supplied via said cable connector and a display means for displaying said signal input from said amplifier;  
       
       
         a microprocessor storing information for an image status being displayed, for selectively switching between internal horizontal and vertical synchronizing signals from an internal generator and external horizontal and vertical synchronizing signals from said external system to provide output horizontal and vertical synchronizing signals having predetermined frequency levels based on a connection status between said signal cable and said cable connector;  
       
       
         means for supplying a plurality of second video signals corresponding to said stored information provided by said microprocessor to said amplifier; and  
       
       
         horizontal and vertical deflection circuits, responsive to said output horizontal and vertical synchronizing signals input from said microprocessor, for supplying horizontal and vertical deflection signals to said display means. 
       
     
     
       22. The video display apparatus of  claim 21 , wherein said predetermined frequency levels are adjustable. 
     
     
       23. A method for self- diagnosis testing of a video display apparatus including a cable connector, a microprocessor, on - screen display circuit and a display screen, said method comprising the steps of:    
       
         checking said cable connector to determine connection to an external system;  
       
       
         generating horizontal and vertical synchronizing frequencies in case of no connection between said cable connector and external system; and  
       
       
         outputting a message display signal to said circuit responsive to an input signal supplied from said microprocessor. 
       
     
     
       24. The method of  claim 23 , wherein said horizontal and vertical synchronizing frequencies are generated by said microprocessor. 
     
     
       25. The method of  claim 23 , wherein said message display signal indicates to a user that there exists no connector between said cable connector and extend system. 
     
     
       26. The method of  claim 25 , wherein said message display signal is pre- stored in said on screen display circuits.   
     
     
       27. The method of  claim 23 , further comprising the steps of: 
       
         detecting an input signal from a key pad; and  
       
         displaying a pre - stored self - diagnostic display on a screen of said cathode ray tube in response to said input signal from said key pad.   
     
     
       28. A video display apparatus, comprising: 
       
         a video device providing displays of variable video images;  
       
       
         a circuit driving said video device to provide said displays; and  
       
       
         a controller monitoring reception of external horizontal and vertical timing signals, generating internal horizontal and vertical timing signals, determining a state of signal connection between said circuit and an external system supplying video signals, and selectively applying to said circuit one of said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals as determined by said controller in dependence upon said state of connection between said circuit and said external system. 
       
     
     
       29. The video display apparatus of  claim 28 , comprising: 
       
         said controller storing information and selectively applying to said circuit video signals representing said information and data controlling horizontal position, vertical position and size of said displays. 
       
     
     
       30. A video display apparatus, comprising: 
       
         a video device providing displays of variable video images;  
       
       
         a circuit disposed to receive externally generated video signals, driving said video device to provide said displays; and  
       
       
         a controller monitoring a connection providing reception of external horizontal and vertical timing signals, generating internal horizontal and vertical timing signals, determining a state of signal connection between said circuit and an external system supplying said externally generated video signals, and selectively applying to said circuit one of said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals as determined by said controller in dependence upon said state of connection between said circuit and said external system. 
       
     
     
       31. The video display apparatus of  claim 30 , comprised of said controller storing information and selectively applying to said circuit internal video signals representing said information and data controlling horizontal position, vertical position and size of said displays. 
     
     
       32. The video display apparatus of  claim 30 , comprised of said controller regulating said circuit to drive said video device to project displays corresponding to said internal video signals when said controller determines the absence of an operational connection between said apparatus and said external system. 
     
     
       33. The video display apparatus of  claim 30 , comprised of said controller regulating said circuit to drive said video device to project displays corresponding to said internal video signals superimposed upon video images corresponding to said external video signals. 
     
     
       34. The video display apparatus of  claim 30 , comprised of said controller regulating said circuit to drive said video device with one display selected by said controller from among said externally generated video signals and said internally generated video signals and image control data. 
     
     
       35. The video display apparatus of  claim 30 , with said circuit comprising: 
       
         a horizontal and vertical deflection stage responding to said image control data and said output horizontal and vertical timing signals by generating vertical deflection signals and horizontal deflection signals;  
       
         an on - screen display generating on - screen video component signals and on - screen blanking signals in correspondence with said image control data and said vertical deflection signals and horizontal deflection signals; and    
         an amplifier driving the display device in dependence upon said externally generated video signals, said on - screen video component signals, and said on - screen blanking signals.   
     
     
       36. The video display apparatus of  claim 30 , further comprised of said controller storing self- diagnostic video information and applying to said circuit video signals representing said self - diagnostic video information in dependence upon said state of connection.   
     
     
       37. The video display apparatus of  claim 36 , further comprised of said controller including key signals selecting one of self- diagnostic video information.   
     
     
       38. The video display apparatus of  claim 30 , further comprised of said controller storing information and applying to said circuit video signals representing a message indicating said state of connection in dependence upon said state of connection. 
     
     
       39. The video display apparatus of  claim 30 , further comprised of said controller monitoring said state of connection by detecting a reference signal generated from said external system. 
     
     
       40. The video display apparatus of  claim 30 , further comprised of said controller determining said state of connection by detecting said external horizontal and vertical synchronization frequency. 
     
     
       41. A video display apparatus, comprising: 
       
         a video device providing displays of variable video images;  
       
       
         a controller monitoring a connection providing reception of external horizontal and vertical timing signals, generating internal horizontal and vertical timing signals, determining a state of signal connection with an external system supplying externally generated video signals, selectively generating internal video signals and image control data, and supplying output horizontal and vertical timing signals selected from among said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals as determined by said controller in dependence upon said state of connection between said circuit and said external system; and  
       
       
         a circuit disposed to receive said externally generated video signals from said external system, driving said video device in response to said output horizontal and vertical timing signals, while under control of said controller to provide said displays in correspondence with selections by said controller from among said externally generated video signals and said internally generated video signals and image control data. 
       
     
     
       42. The video display apparatus of  claim 41 , comprised of said controller regulating said circuit to drive said video device to project displays corresponding to said internal video signals when said controller determines the absence of an operational connection between said apparatus and said external system. 
     
     
       43. The video display apparatus of  claim 41 , comprised of said controller regulating said circuit to drive said video device to project displays corresponding to said internal video signals superimposed upon video images corresponding to said external video signals. 
     
     
       44. The video display apparatus of  claim 41 , comprised of said controller regulating said circuit to drive said video device with one display selected by said controller from among said externally generated video signals and said internally generated video signals and image control data. 
     
     
       45. The video display apparatus of  claim 41 , with said circuit comprising: 
       
         a horizontal and vertical deflection stage responding to said image control data and said output horizontal and vertical timing signals by generating vertical deflection signals and horizontal deflection signals;  
       
         an on - screen display generating on - screen video component signals and on - screen blanking signals in correspondence with said image control data and said vertical deflection signals and horizontal deflection signals; and    
         an amplifier driving the display device in dependence upon said externally generated video signals, said on - screen video component signals, and said on - screen blanking signals.   
     
     
       46. The video display apparatus of  claim 41 , comprised of said controller monitoring said connection by detecting a logic state of a synchronization ground signal supplied by said connection. 
     
     
       47. A video display process, comprising: 
       
         arranging an operational connection to receive externally generated video signals and externally generated horizontal and vertical timing signals;  
       
       
         monitoring a connection providing reception of said external horizontal and vertical timing signals;  
       
       
         generating internal horizontal and vertical timing signals;  
       
       
         making a determination of a state of said operational connection;  
       
       
         selectively transmitting one of said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals in dependence upon said determination of said state of connection; and  
       
       
         driving a video device to provide visual displays of variable video images, in correspondence with said one of said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals transmitted. 
       
     
     
       48. The video display process of  claim 47 , comprised of storing information and selectively applying to said video device signals representing said information and data controlling horizontal position, vertical position and size of said visual displays. 
     
     
       49. The video display process of  claim 47 , comprised of controlling said video device to project displays corresponding to said internal video signals when said determination indicates an absence of an operational connection providing said external horizontal and vertical timing signals. 
     
     
       50. The video display process of  claim 47 , comprised of storing second video signals representing predetermined images, and driving said video device to project displays corresponding to said second video signals superimposed upon video images corresponding to said external video signals. 
     
     
       51. The video display process of  claim 47 , comprised of storing second video signals representing predetermined images and image control data indicative of parameters of said displays, and driving said video device with one display selected from among said externally generated video signals and said second video signals and image control data. 
     
     
       52. The video display process of  claim 47 , comprising: 
       
         storing second video signals representing predetermined images and image control data indicative of parameters of said displays;  
       
       
         responding to said image control data and said one of said external horizontal and vertical timing signals and internal horizontal and vertical timing signals selectively transmitted, by generating vertical deflection signals and horizontal deflection signals;  
       
         generating on - screen video component signals and on - screen blanking signals in correspondence with said image control data and said vertical deflection signals and horizontal deflection signals; and    
         driving the display device in dependence upon said externally generated video signals, said on - screen video component signals, and said on - screen blanking signals.   
     
     
       53. The video display process of  claim 47 , comprised of monitoring said connection by detecting a logic state of a synchronizing ground signal supplied by said connection. 
     
     
       54. The video display apparatus of  claim 47 , comprised of said controller monitoring said connection by detecting a logic stage of a synchronization ground signal supplied by said connection. 
     
     
       55. A video display process, comprising: 
       
         arranging an operational connection to receive externally generated video signals and externally generated horizontal and vertical timing signals;  
       
       
         monitoring a connection providing reception of said externally generated horizontal and vertical timing signals;  
       
       
         generating internal horizontal and vertical timing signals;  
       
       
         making a determination of a state of said operational connection with an external system supplying said externally generated video signals;  
       
       
         selectively generating internal video signals and image control data;  
       
       
         transmitting output horizontal and vertical timing signals selected from among said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals as in dependence upon said determination of said state of said operational connection between said circuit and said external system; and  
       
       
         driving said video device in response to said output horizontal and vertical timing signals, while under control to provide said displays in correspondence with selections from among said externally generated video signals and said internally generated video signals and image control data. 
       
     
     
       56. The video display process of  claim 55 , comprised of storing information and selectively applying to said video device signals representing said information and data controlling horizontal position, vertical position and size of said visual displays. 
     
     
       57. The video display process of  claim 55 , comprised of controlling said video device to project displays corresponding to said internal video signals when said determination indicates an absence of an operational connection providing said external horizontal and vertical timing signals. 
     
     
       58. The video display process of  claim 55 , comprised of storing second video signals representing predetermined images, and driving said video device to project displays corresponding to said second video signals superimposed upon video images corresponding to said external video signals. 
     
     
       59. The video display process of  claim 55 , comprised of storing second video signals representing predetermined images and image control data indicative of parameters of said displays, and driving said video device with one display selected from among said externally generated video signals and said second video signals and image control data. 
     
     
       60. The video display process of  claim 55 , comprising: 
       
         storing second video signals representing predetermined images and image control data indicative of parameters of said displays;  
       
       
         responding to said image control data and said one of said external horizontal and vertical timing signals and internal horizontal and vertical timing signals selectively transmitted, by generating vertical deflection signals and horizontal deflection signals;  
       
         generating on - screen video component signals and on - screen blanking signals in correspondence with said image control data and said vertical deflection signals and horizontal deflection signals; and    
         driving the display device in dependence upon said externally generated video signals, said on - screen video component signals, and said on - screen blanking signals.   
     
     
       61. The video display process of  claim 55 , comprised of monitoring said connection by detecting a logic state of a synchronization ground signal supplied by said connection. 
     
     
       62. A video display apparatus, comprising: 
       
         a video device providing displays of variable video images;  
       
       
         a controller monitoring a connection providing separate and individual reception of externally generated video signals, external horizontal and vertical timing signals and a synchronization ground signal, generating internal horizontal and vertical timing signals, determining a state of said connection, selectively generating internal video signals, and supplying output horizontal and vertical timing signals selected from among said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals as determined by said controller in dependence upon said state of connection; and  
       
       
         a circuit disposed to receive said externally generated video signals, driving said video device in response to said output horizontal and vertical timing signals, while under control of said controller to provide said displays in correspondence with selections by said controller from among said externally generated video signals and said internally generated video signals and image control data. 
       
     
     
       63. The video display apparatus of  claim 62 , further comprised of said controller regulating said circuit to drive said video device to project displays corresponding to said internally generated video signals when said controller determines the absence of said connection. 
     
     
       64. The video display apparatus of  claim 62 , further comprised of said controller regulating said circuit to drive said video device to project displays representing a disconnection when said controller determines the absence of said connection. 
     
     
       65. The video display apparatus of  claim 62 , further comprised of said controller regulating said circuit to drive said video device to project displays representing self- diagnostic information when said controller determines the absence of said connection.   
     
     
       66. The video display apparatus of  claim 62 , further comprised of said controller storing information and selectively applying to said circuit video signals representing said information and data controlling horizontal position, vertical position, and size of said displays. 
     
     
       67. The video display apparatus of  claim 62 , further comprised of a key pad generating a key signal selecting one of internally generated video signals and image control data. 
     
     
       68. The video display apparatus of  claim 62 , further comprised of said controller monitoring said connection by detecting a logic state of said synchronization ground signal supplied by said connection. 
     
     
       69. A video display process, comprising: 
       
         arranging an operational connection to separately and individually receive externally generated video signals, externally generated horizontal and vertical timing signals, and a synchronization ground signal;  
       
       
         monitoring a state of said connection;  
       
       
         generating internal horizontal and vertical timing signals;  
       
       
         making a determination of a state of said operational connection;  
       
       
         selectively transmitting one of said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals in dependence upon said determination of said state of connection; and  
       
       
         driving a video device to provide visual displays of variable video images, in correspondence with said one of said external horizontal and vertical timing signals and said internal horizontal and vertical timing signals transmitted. 
       
     
     
       70. The video display process of  claim 69 , further comprised of the step of driving said video device to project displays corresponding to said internally generated video signals in dependence upon said determination. 
     
     
       71. The video display process of  claim 69 , further comprised of the step of driving said video device to project displays representing said disconnection in dependence upon said determination. 
     
     
       72. The video display process of  claim 69 , further comprised of the step of driving said video device to project displays representing self- diagnostic information in dependence upon said determination.   
     
     
       73. The video display process of  claim 69 , further comprised of the step of storing information and selectively applying to said video device video signals representing said information and data controlling horizontal position, vertical position, and size of said displays in dependence upon said determination. 
     
     
       74. The video display process of  claim 69 , further comprised of the step of generating a key signal selecting one of said video images. 
     
     
       75. The video display process of  claim 69 , further comprised of the step of making said determination of said state of connection by detecting a logic state of said synchronization ground signal of said connection. 
     
     
       76. A video display apparatus, comprising: 
       
         a video display device providing displays of variable video images; and  
       
       
         a controller connected to said video display device, monitoring an operational connection providing reception of externally generated signals for said video images, determining a state of said connection, generating an internal video signal in dependence upon said state of said connection, applying to said video display device said internal video signal for said video image. 
       
     
     
       77. The video display apparatus of  claim 76 , further comprised of said internal video signal being one of a self- diagnostic image signal and a message signal indicating said state of said connection.   
     
     
       78. The video display apparatus of  claim 77 , further comprised of a key pad generating a key signal selecting one of a plurality of self- diagnostic images.   
     
     
       79. The video display apparatus of  claim 76 , further comprised of said controller storing information and selectively applying to said video display device internal video signals representing said information controlling horizontal position, vertical position, and size of said displays in dependence upon said state of said connection. 
     
     
       80. The video display apparatus of  claim 79 , further comprised of a key pad generating a key signal adjusting said information. 
     
     
       81. The video display apparatus of  claim 76 , further comprised of said controller generating internal timing signals for video image said video signal, supplying said internal timing signal signals to said video display device in dependence upon said state of said connection. 
     
     
       82. The video display apparatus of  claim 76 , further comprised of said controller monitoring said connection providing separate and individual reception of externally generated video signal, external timing signal, and a reference signal. 
     
     
       83. The video display apparatus of  claim 82 , further comprised of said controller monitoring said connection by detecting a logic state of said reference signal. 
     
     
       84. The video display process, comprising the steps of: 
       
         monitoring an operational connection providing reception of externally generated signals;  
       
       
         making a determination a state of said connection;  
       
       
         generating an internal video signal in dependence upon said determination of said state of said connection; and  
       
       
         applying said internal video signal to a video display device providing displays of video images. 
       
     
     
       85. The video display process of  claim 84 , further comprised of the step of applying to said video display device one of a self- diagnostic image signal and a message signal indicating said state of said connection in dependence upon said determination of said state of said connection.   
     
     
       86. The video display process of  claim 85 , further comprised of the step of generating a key signal selecting one of a plurality of self- diagnostic images.   
     
     
       87. The video display process of  claim 84 , further comprised of the step of said storing information and selectively applying to said video display device internal video signals representing said information controlling horizontal position, vertical position, and size of said displays in dependence upon said state of said connection. 
     
     
       88. The video display process of  claim 87 , further comprised of the step of generating a key signal adjusting said information. 
     
     
       89. The video display process of  claim 84 , further comprised of generating internal timing signals for a video image corresponding to said video signal, and supplying said internal timing signal signals to said video display device in dependence upon said state of said connection. 
     
     
       90. The video display process of  claim 84 , further comprised of the step of said monitoring said connection providing separate and individual reception of externally generated video signals, external timing signal, and a reference signal. 
     
     
       91. The video display process of  claim 90 , further comprised of monitoring said connection by detecting a logic state of said reference signal.