1. Field of the Invention
The invention relates to a device and a method for repeatedly updating the function of a monitor, and more particularly to a device and a method for repeatedly updating the function of a monitor by using universal serial bus signal lines for signal transmission.
2. Description of the Related Art
In a current monitor system, a monitor controller must be exchanged when function modifying or debugging, resulting in high cost consumed. As to a further advanced monitor system, a corresponding monitor controller has a build-in read only memory (ROM) which is an erasable programmable read only memory. By updating data stored in the erasable programmable read only memory, function modification and debugging can be achieved.
Referring to FIG. 1, a conventional monitor is shown. The monitor has a total of 18 VGA signal lines electrically coupled to a VGA card, which includes a vertical synchronous signal (Vsync) line, a horizontal synchronous signal (Hsync) line, a serial data (SDA) line, a serial clock (SCL) line, a ground (Gnd) line, a red (R) line, a green (G) line and a blue (B) line. During a normal operation, a monitor controller 10 having a ROM is electrically coupled to a horizontal and vertical deflection device 20 via a first jumper 14 and to an on screen display 50 via a second jumper 16. The monitor controller 10 is electrically coupled to the a voltage source (5 V) via a power supply jumper 12. The Hsync, Vsync, SDA, SCL and Gnd signal lines are electrically coupled to the monitor controller 10 for driving the horizontal and vertical deflection device 20 according to a received signal and a program stored in the ROM and further controlling a vertical booster (Vert. Booster) 30 and a horizontal booster (Hori. Booster) 40 for CRT horizontal and vertical controls. A on screen display driving circuit 50 is used to put control ICON to a video pre-amplifier 60. After that, the R, G, B signals are transmitted to a video amplifier 70 from the video pre-amplifier 60 and then displayed on a display (not shown).
When it is necessary to modify the function of the monitor system, data stored in the ROM of the monitor controller 10 needs to be updated. First, the case of the monitor must be opened. Then, the first jumper 14 and the second jumper 16 are switched to electrically connect the monitor controller 10 to a recording connector 80 and a voltage source (12 V). Next, a ROM writer (not shown) is electrically coupled to the recording connector 80 for data update.
Referring now to FIG. 2, a conventional system being able to update the function of a monitor is shown. After opening the case of a monitor 100, the recording connector 80 and the VGA signal line 18 can be found on a printed circuit board 110. The first jumper 14, the second jumper 16 and the power supply jumper 12 which can be found on a jumper region 22 are switched. In a memory recording system 90, a ROM writer 92 is controlled by a computer 94 and a display 96 is used to monitor the condition of recording. Finally, the ROM writer 92 is electrically coupled to the recording connector 80 for recording the ROM of the monitor controller 10 using the computer 94 thereby to update the monitor system.
Obviously, it is really inconvenient to update the monitor system because the case of the conventional monitor must be opened, first and then jumpers are switched for recording the erasable programmable read only memory of the monitor controller 10.
Today, monitors have been speedily developed. Especially, liquid crystal displays have been mass produced. To increase the speeds of the operation of monitors, universal serial bus (hereinafter, referred to as USB) is used for signal transmission. Referring to FIG. 3, a block circuit diagram of a monitor system having USB signal lines is shown. In addition to conventional VGA signal lines 18, USB signal lines 19 are further used to replace serial data and serial clock signals on the VGA signal lines 18. The USB signal lines 19 includes a power source Vcc, a ground Gnd and two data signal lines D+, D−. The data signal lines D+, D− are used to transmit monitor command data. The speed of the USB can be increased up to 1.2 M Bps. As a result, the speed of the operation of the monitor can be greatly increased.
Similarly, it causes inconvenience when the monitor system is updated because it is necessary to open the case of the monitor and to switch jumpers for recording the erasable programmable read only memory of the monitor controller 10.