CN2181029Y

CN2181029Y - TV/computer two-purpose display disc

Info

Publication number: CN2181029Y
Application number: CN 94206998
Authority: CN
Inventors: 王宇鹏
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-03-22
Filing date: 1994-03-22
Publication date: 1994-10-26
Anticipated expiration: 2004-03-22

Abstract

The utility model relates to a computer displaying device which is designed for computer and TV two-purpose display, and combines the structures of the existing VGA card and the CTV card. The utility model is formed by the combination of a VGA controller, a clock, a BIOS sheet, a DRAM, an analog-digital converter RAMDAC, a logic mixing module of R, G, B, H and V signals, a video modulator, a high frequency head and an N/P system transfer switch. The structure modulates the R, G and B signals of a computer into standard TV signals, is simultaneously provided with a TV high-frequency and a VGA standard output two ports, and can be simultaneously connected with a monitor of the computer and the ordinary TV or only connected with one of the monitor and the ordinary TV. The utility model has the advantages of compact design and flexible use.

Description

TV/computer two-purpose display disc

The utility model relates to a kind of computer output device, relates to a kind of calculator display organization or rather.

The VGA display card that uses on the computing machine, be used for having extraordinary display effect when computing machine shows, but the graphoscope price is more expensive, being unsuitable for family uses, for making computer can enter family, make colour TV can be used as the color monitor of computing machine again by TV reception, and designed a kind of telecomputer transition card (CTV card), with regard to available common domestic TV substituting for computer display, make colour TV become the color monitor of computing machine.

Transition card is converted to television video, radio frequency analog signal with the digital displaying signal of computing machine output, the numeral that the televisor of having popularized in the family can be demonstrated only could show on the computing machine special-purpose terminal and visual.The additional transition card on computers of this kind though solved the problem of available television machine as computer color display, can not be used for the demonstration of the former display of computing machine simultaneously, makes troubles to use.

The purpose of this utility model is design a kind of computer/TV dual purpose display card, the VGA card structure and the computer/TV conversion CTV card structure of existing computer are combined, this card is additional on computers, both the available television machine was as the picture and text display terminal of computing machine, available again monitor is as the display terminal of computing machine, both can use simultaneously, also can appoint one.

Computer of the present utility model/TV dual purpose display card, it is characterized in that: comprise the VGA display controller that is connected across on the computer AT-bus, the clock module of system clock and read clock is provided to the VGA display controller, support the basic function of VGA, the standard driver module BIOS of advanced interface is provided for dos operating system, be used for providing the display buffer memory DRAM that shows information needed to VGA, computer R with VGA output, G, the B digital signal converts R to, G, the digital to analog converter RAMDAC of B simulating signal, capable H signal with display controller VGA output, the R of field V signal and digital to analog converter RAMDAC output, G, the B analog signal conversion becomes can be fit to the TV modulation logic mixing module of video modulator signal form, R with the output of logical hybrid module, G, B, the HV signal is modulated into the video modulator of vision signal, vision signal is modulated into the tuner RF of TV RF signals, R with digital to analog converter RAMDAC output, G, the H of B simulating signal and the output of VGA display controller, the VGA standard output port that V signal is connected with display monitor central monitoring system is with the television high frequency output port that the radiofrequency signal of tuner output can be connected with televisor.

The video modulator periphery can increase P/N system conversion switch that is used for PAL and the conversion of TSC-system formula and the fine setting controller that improves the video modulation effect.

The utility model is modulated into the standard TV receiver signal with R, G, the B signal of computer, and has television high frequency output and two ports of VGA standard output simultaneously, has increased the use dirigibility.This dual purpose display card can complete compatible IBM PC-AT VGA standard, has super VGA(SVGA) function, highest resolution is 1024 * 768, can use common domestic TV, support NTSC, pal mode simultaneously, if, can have audio frequency sound accompaniment function simultaneously to tuner send audio AUDIO signal.

Describe technology of the present utility model in detail below in conjunction with the embodiment accompanying drawing

Fig. 1. computer/TV dual purpose display card logic schematic diagram

Fig. 2. logical block 101,105 is implemented circuit diagram among Fig. 1

Fig. 3. logical block 102 is implemented circuit diagram among Fig. 1

Fig. 4. logical block 103 is implemented circuit diagram among Fig. 1

Fig. 5. logical block 106-110 implements circuit diagram among Fig. 1

Referring to Fig. 1,111 is AT-bus among the figure, with the AT-bus of computing machine 400 and connect.101 is display controller VGA, is the core component of dual purpose display card.102 is dynamic storage DRAM, is the display buffer memory of VGA display controller, is used to store the required various information of demonstration.103 is digital to analog converter RAMDAC, is special and the matching used special digital to analog converter of VGA display controller.104 is clock module, is a doubleclocking frequency synthesizer, provides required system clock and read clock to VGA display controller 101.105 for showing the BIOS module, is solidified with the standard driver, is mainly used in the basic function of control VGA display controller, comprises the demonstration of display system initialization, display mode switching, character and point etc., for dos operating system provides an advanced interface.106 is TV modulation logic mixing module, R, G, B, H, V signal is converted to signal form R, G, B, the HV that is fit to video modulator 107.107 is video modulator, and output video VIDEO signal is to radio-frequency modulator RF(tuner) 108, terminal is arranged for inserting AVDIO audio frequency audio signal, insert tuner 108 simultaneously, final modulation output is fit to the radiofrequency signal that televisor 300 receives.

Can select for use televisor to show flexibly for making this dual purpose display card, can support NTSC and pal mode simultaneously, and be that video modulator 107 has been equipped with P/N system conversion switch 109, the 3.58M oscillation frequency that can select to be applicable to the 4.433M oscillation frequency of pal mode respectively and be applicable to the TSC-system formula.Fine setting controller 110 is used to finely tune the required auxiliary signal of video modulator 107, makes the vision signal effect after modulated better.

This dual purpose display card has port one 12 that is connected with monitor 200 and the port one 13 that is connected with televisor 300.

Logical block 101-105,107,108 shown in Fig. 1 all finishes its function to integrated chip or finished product that special use should be arranged, so its enforcement circuit is very simple, clear, and volume is little, and performance is good, transfers and surveys conveniently.

After system opens, the clock module 104 of this dual purpose display card provides system clock and read clock for VGA display controller 101, CPU in the VGA display controller 101 calls software among the standard driver module BIOS105 by AT-bus, the initialization VGA of elder generation display controller 101, afterwards, the user-operable host keyboard is by BIOS or direct control VGA display controller 101, the video information that needs are shown deposits among the DRAM102 of display buffer by VGA display controller 101, the conversion of signals that VGA display controller 101 obtains after with periodic scan display buffer DRAM102 by the hardware circuit in it becomes the output of TTL vision signal, and convert to through digital to analog converter RAMDAC103 and to be suitable for the analog video signal R that monitor 200 receives, G, B(Red, Green, Blue), this R, G, B signal one tunnel send monitor 200 through port connector 112, and TV modulation logic mixing module 106 is sent on another road.Send into capable H, a V signal that also having of TV modulation logic mixing module 106 exported through VGA display controller 101 simultaneously, the TV modulation logic is mixed mould mould 106 and is converted R, G, B, H, V signal to video modulator 107 video R, the G that can receive, B signal and HV control signals, video modulator 107 is processed into the standard television signal of pal mode or NTS standard with them, convert to and can also can send televisor 300 to show through concentric cable through radio-frequency modulator RF108 again by the TV signal of antenna emission by port connector 113.

Referring to Fig. 2, be the enforcement circuit diagram of VGA display controller logical block 101 among Fig. 1 and demonstration BIOS module 105.

Connector J1 inserts the computer AT-bus in the dual purpose display card, and integrated impact damper U6, U9 and integrated VGA chip U7 constitute VGA display controller 101.Prom memory U8 constitutes BIOS module 105.System clock DRAMCK and read clock VIDEOCK from clock module 104 are imported by 89,91 ends of U7 respectively.The MO2D(0..7 of U7), DM02A(0..7 DM13A(0..7 M13D(0..7))) and DRAS, DCAS, WE02, the DRAM102 of WEI3 \ signal and Fig. 3 each be connected with each end.The BLANK of U7, VSYNC, HSYNC, PCLK, P(0..7) signal is connected with each end of the same name of digital to analog converter RAMSAC103 of Fig. 4.

Referring to Fig. 3, be the enforcement circuit of dynamic storage DRAM102 among Fig. 1, constitute by the integrated dynamic storage U1-U4 parallel connection of 4 512K bytes.

Referring to Fig. 4, enforcement circuit for Fig. 1 logical block digital to analog converter 103, constitute by integrated video D/A controller U5 and peripheral cell thereof, its P(0..7) termination is gone into the video TTL signal by 101 outputs of Fig. 2 VGA display controller, AD(0..7), SA(0..19), DACWR, BLANK, DACRD, the PCLK end is connected with the end of the same name of VGA101 among Fig. 2, the R of U5, G, the B end is exported the R through the D/A conversion respectively, G, the B signal is with capable synchronous from the HSYNC(of Fig. 2 display controller U7), the VSYNC(field synchronization) signal is connected on the port CN1 connector 112 together.

Referring to Fig. 5, be the enforcement circuit of TV modulation logic mixing module 106, video modulator 107, tuner 108, PAL/NTSC standard converter 109 and fine setting controller 110 among Fig. 1.

Constitute TV modulation logic mixing module 106 by XOR gate VU2, resistance VR2, VR5, VR8, VR1, VR4, VR7 and electric capacity VC3, VC4, VC5, will be RIN, GIN, BIN signal from R, G, the B signal shaping of U5 among Fig. 4 and will be the HVSYN signal from HSYNC, the VSYNC signal combination of Fig. 2 U7.

By integrated video modulator U9(MC1377) and peripheral cell formation video modulator 107, output video VIDEO signal also can insert tuner RF108 AUDIO end through adjustable resistance W2, coupling capacitance VC16 tremendously high frequency head RF108 VIDEO end simultaneously from the audio frequency audio signal AUDIO of port input.

P/N system conversion switch JPV2, JPV1 and VC12-VC15, CV1, crystal resonator VX1 are the circuit structures that provides on the MC1377 product manual, and toggle switch by the circuit in integrated, can be selected the oscillation frequency of 3.58M or 4.433M.

The enforcement circuit of fine setting controller 110 is by resistance VR18,9V stabilivolt D1, adjustable resistance W1, resistance VR20, the electronic tuning circuit that filter capacitor VC17, current-limiting resistance VR19 and varactor D2 constitute.By adjusting W1, the dividing potential drop that changes W1 and VR20 promptly changes D2 and goes up voltage, reaches the effect of capacitance value, fine setting oscillation frequency.

Compact to design, the novel structure of dual purpose display card of the present utility model, the convenient use enters family for computer is universal and created condition.

Claims

1, a kind of computer/TV dual purpose display card, it is characterized in that: comprise the VGA display controller that is connected across on the computer AT-bus, the clock module of system clock and read clock is provided to the VGA display controller, support the basic function of VGA, the standard driver module BIOS of advanced interface is provided for dos operating system, be used for providing the display buffer memory DRAM that shows information needed to VGA, computer R with VGA output, G, the B digital signal converts R to, G, the digital to analog converter RAMDAC of B simulating signal, capable H signal with display controller VGA output, the R of field V signal and digital to analog converter RAMDAC output, G, the B analog signal conversion becomes can be fit to the TV modulation logic mixing module of video modulator signal form, R with the output of logical hybrid module, G, B, the HV signal is modulated into the video modulator of vision signal, vision signal is modulated into the tuner RF of TV RF signals, R with digital to analog converter RAMDAC output, G, the H of B simulating signal and the output of VGA display controller, the VGA standard output port that V signal is connected with display monitor central monitoring system is with the television high frequency output port that the radiofrequency signal of tuner output can be connected with televisor.

2, computer according to claim 1/TV dual purpose display card, it is characterized in that described video modulator is the MC1377 integrated chip, also include NTSC/PAL system conversion switch that is connected with video modulator and the fine setting controller that is used to improve modulation effect.

3, computer according to claim 1/TV dual purpose display card is characterized in that also comprising an audio A UDIO input port, and port is connected with the AUDIO end of described tuner RF.

4, computer according to claim 2/TV dual purpose display card, it is characterized in that described fine setting controller is a turning device, the bleeder circuit of connecting that comprises resistance and voltage stabilizing diode, the resistor voltage divider circuit that is connected with the voltage stabilizing diode negative terminal, the adjustable side of resistor voltage divider circuit adjustable resistance connects filter capacitor over the ground and connects the series circuit of current-limiting resistance and varactor, and the varactor negative terminal connects external crystal oscillator one end of video modulator.