Touch screen common fault analysis - Database & Sql Blog Articles

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I believe that many people use the touch screen when they encounter the failure of the touch screen due to malfunction. This is mainly because the touch screen is a relatively sophisticated device, and the touch screen is mostly open to the public. Its high frequency of use and the quality of its users are mixed, which causes its faults to occur frequently. Here are some common faults of the touch screen. Solution and maintenance methods:
When the touch screen fails, you should first check whether the power supply of the control card is normal, whether the Windows driver is installed normally, and then check whether the touch screen calibration under Windows is completed. If the parameters in the “TouchscreenControl” are correct, you need to check whether the serial port is normal and the serial port. Whether the line is connected properly.
The following describes some examples of the diagnosis and treatment of touch screen failures.
1. The touch screen is not allowed
[Fault phenomenon]
A surface acoustic wave touch screen that touches the display screen with a finger does not normally perform the corresponding operation.
[Fault Analysis Processing]
This phenomenon may be caused by the sound wave touch screen being covered by dust after being used for a period of time. It can be wiped with a dry soft cloth, then power off, restart the computer and recalibrate. It is also possible that the reflection fringes of the sound wave screen are slightly damaged, and if this is the case, it will not be completely repaired.
If it is a capacitive touch screen, the screen calibration program can be run under the following conditions: (Start--Program--MicrotouchTouchware)
1) Complete the installation of the driver software for the first time.
2) After changing the resolution or display mode of the display.
3) After changing the displayed display area each time.
4) After adjusting the frequency of the controller each time.
5) Each time the cursor does not correspond to the touch point.
After calibration, the calibrated data is stored in the controller's registers, so there is no need to calibrate the screen each time the system is turned on.
2. The touch screen is not responding
[Fault phenomenon]
A touch screen does not work and does not respond to any part of the touch.
[Fault Analysis Processing]
First check if the wiring interface is loose, then check if there is any conflict between the serial port and the interrupt number. If there is any conflict, adjust the resources to avoid conflicts. Then check the surface of the touch screen for cracks. If there is any crack, it should be replaced in time. Also check the surface of the touch screen for dirt and, if so, clean it with a soft cloth. Observe that the indicator light on the control box is working properly. When it is normal, the indicator light is green and blinks.
If the above parts are normal, you can use the replacement method to check the touch screen, replace the control box first, then replace the touch screen, and finally replace the host.
If it is a surface acoustic wave touch screen, it can be repaired as follows:
1) It may be the connection of the touch screen. One of the connections to the keyboard port of the host computer (the 5 volt touch screen operating voltage from the keyboard port) is not connected. Please check the connection.
2) It may be that the serial port number selected during the driver installation process of the touch screen does not correspond to the serial port number actually connected to the touch screen. Please uninstall the driver and reinstall it.
3) It may be that the host is a domestically produced original machine. The installed operating system is an OEM version, which has been adjusted by the manufacturer, resulting in non-standard serial communication. It is not compatible with the touch screen driver. If possible, format the hard disk and drive the touch screen after installing the system. .
4) It is possible that the touch screen driver version is too low. Please install the latest driver.
5) Is there any equipment in the host that conflicts with the serial port resources? Check each hardware device and adjust it. For example, after some network cards are installed, the default IRQ is 3, which conflicts with the IRQ of COM2. In this case, the IRQ of the network card should be changed to the unused IRQ. .
If it is a resistive touch screen, it can be repaired as follows:
1) Check if the connection of the touch screen is connected. One of the connections to the keyboard port of the host (take the 5 volt touch screen working voltage from the keyboard port) is not connected. Please check the connection.
2) Observe the condition of the touch screen control box light. If it is not lit or the red light is on, the control box is broken and please replace it.
3) If the confirmation is not the above, please delete the touch screen driver and restart the computer to reinstall the driver, or replace the driver with a newer version.
4) Is there any equipment in the host that conflicts with the serial port resources? Check each hardware device and adjust it. For example, after some network cards are installed, the default IRQ is 3, which conflicts with the IRQ of COM2. In this case, the IRQ of the network card should be changed to the unused IRQ. It may be that the computer motherboard and the touch screen control box are not compatible. Please replace the main unit or the motherboard.
5) If the touch screen has been used for a long period of time (3-4 years) and some areas of the touch screen cannot be touched, it may be that the touch screen is broken, please replace the touch screen.
If it is a capacitive touch screen, it can be repaired as follows:
1) Check if the connection of the touch screen is connected. If it is an external box control card, the control box part is connected directly to the cable extending from the touch screen through the return slot. The power supply part passes through a keyboard conversion head (must be The small rubber head next to the RS232 port connector can be pulled out before the power can be connected. Connect one end to the keyboard port of the main unit and the other end to the computer keyboard. Insert a small head of the 5V power supply into the 232. The connection of the port will connect the RS232 connector of the control box to the 9-pin hole of the host. If your host can use the 25-pin hole, please purchase the 9-25 adapter for conversion. If your host's keyboard The mouth is the keyboard port of the original machine, please buy a pair of large keyboard to the adapter of the keypad.
2) If it is a built-in card type, check whether the jumper jumps to the jumper of the control card. Since the user's machine configuration is different, the peripherals used at the same time are different. Therefore, in order to avoid the conflict between the touch screen and the user's peripherals, MicroTouch provides the jumper description of the control card for the customer to choose. The control card address jumper setting instructions:
COM port settings
CommPortI/OA1A2A3A4A5A6
COM13F8-3FFONOFFONOFFONOFF
COM22F8-2FFOFFONONOFFONOFF
COM33E8-3EFONOFFOFFONONOFF
COM42E8-2EFOFFONOFFONONOFF
COM52E0-3E8OFFONOFFONOFFON
COM62F0-2F8OFFONONOFFOFFON
COM73E0-3E8ONOFFOFFONOFFON
COM83F0-3F8ONOFFONOFFOFFON
The combination of the COM port and the interrupt jumper should be set as follows. Special cases are exceptional.
COM1->IRQ4|COM2->IRQ3|COM3->IRQ4|COM4->IRQ3
3. The touch screen response time is very long
[Fault phenomenon]
A touch screen, after touching the display screen with a finger, takes a long time to react.
[Fault Analysis Processing]
It is possible that there is a moving water droplet on the touch screen, just wipe it with a dry soft cloth. It is also possible that the host level is too low, such as the clock frequency is too low, if this is the case, it is best to replace the host.
4. The touch screen is partially unresponsive
[Fault phenomenon]
A touch screen, after touching the display screen with a finger, the local area is not responding.
[Fault Analysis Processing]
It is possible that the touch screen reflection stripe is partially covered and can be wiped clean with a dry soft cloth. It is also possible that the reflective stripe of the touch screen is partially scraped off by a hard object and will not be repaired.
5. The touch screen is normal but the computer cannot operate
[Fault phenomenon]
A touch screen, after testing itself, everything is normal, but after connecting to the host, the computer can not operate.
[Fault Analysis Processing]
This may be because the touch screen control card receives the operation signal before the host starts loading the touch screen driver, and only needs to restart the computer after restarting the power. It is also possible that the touch screen driver version is too low and you need to install the latest drivers. #p#分页头#e#
6. After the driver is installed, the touch screen is not responded for the first time.
[Fault phenomenon]
A touch screen, the first time you start the touch screen after installing the driver, it will not respond.
[Fault Analysis Processing]
First make sure that the touch screen line connection is correct. If it is not correct, connect all lines correctly after shutting down. Then check whether there is any conflict between the device and the serial port resources in the host. Check each hardware device and adjust them. For example, after some network cards are installed, the default IRQ is 3, which conflicts with the IRQ of COM2. In this case, the IRQ of the network card should be changed to idle. IRQ.
7. After using for a while, the touch does not respond.
[Fault phenomenon]
A touch screen will not respond after a period of normal use after booting.
[Fault Analysis Processing]
1) Check if the hard disk is turned off in the "Monitor Energy Saving Settings" of the Windows 9x. The method is to right-click on the desktop, select the "Properties" command, then select the "Screen Saver" tab from the dialog box, click the "Settings" button, set the parameter to "Always open" except "Power Scheme" In addition, the rest are “never”.
2) In some applications, due to poor grounding performance, the control box housing is covered with a large amount of static electricity, which affects the working electric field inside the control box, resulting in the gradual failure of the touch. At this point, use a wire to ground the control box housing and restart it.
3) Since the surface of the touch screen is covered with sound waves when the surface acoustic wave touch screen is working, if the touch screen is not rubbed for a long time, the dust accumulates too much, blocking the reflection stripe of the wave, and the touch screen cannot work normally. For touch displays, use a clean business card or banknote to gently wipe off the dust from the surrounding reflective strips through the gap between the front cover and the touch screen, and then restart the computer. For the touch-sensitive unit, open the front cover of the monitor, wipe the dust off the reflective strips with a clean towel, and then restart the computer.
4) Many touch-one machine touch screen control boxes adopt the method of taking power from the integrated machine power instead of taking power from the host. Therefore, it is also necessary to check whether the 5V output of the all-in-one power supply is correct, and sometimes the instantaneous current is too large, causing the fuse to be burned. The fuse needs to be replaced.
8. Touch screen click accuracy is reduced
[Fault phenomenon]
With a touch screen, the click accuracy is reduced and the cursor is difficult to position.
[Fault Analysis Processing]
1) Run the touch screen calibration program. (Start - Settings - Control Panel - Sound Screen - Capberate button).
2) If it is a newly purchased touch screen, please try to delete the driver, then power off the host for 5 seconds to reinstall the driver.
3) If the above method does not work, it may be that the reflection fringes of the acoustic screen are slightly damaged during transportation and cannot be completely repaired. You can deviate from the calibration target by the opposite direction (relative to the direction of the mouse).
4) If the sound wave screen is not allowed after a period of use, it may be that the reflective stripes around the screen or the transducer is covered with dust. If you are using our KA type cabinet, you can open the top cover with a dry one. Soft cloth, industrial alcohol or glass cleaning solution to clean the surface, and then re-run the system, pay attention to the upper left, upper right, lower right transducer can not be damaged. Then power off and restart the computer and recalibrate.
5) There are water drops or other soft things on the surface of the touch screen stuck to the surface. The touch screen misjudges that the surface sound wave screen is inaccurate due to hand touch, and it can be cleared.
The touch screen cannot be calibrated
[Fault Analysis Processing]
1) If you are using a Lenovo host, the pre-installed MOUSEWARE software conflicts with the touch screen driver. Please remove this software and restart the running calibration program.
2) It is possible that the touch screen control card receives an operation signal before the host starts loading the touch screen driver. Please power off the computer and recalibrate.
3) It may be that the touch screen driver installation is abnormal. Please delete the driver and reinstall it. (Delete from the control panel add remove program.)
4) It may be that after the sound wave screen is used for a period of time, the reflective stripe around the screen is covered with a large amount of dust and cannot be calibrated. If you are using our KA type cabinet, you can open the top cover with a dry soft cloth. Wipe, pay attention to the upper left, upper right, lower right transducer can not be damaged. Start the computer and calibrate.
9. The mouse stays at a certain point on the touch screen.
[Fault Analysis Processing]
This happens because the touch area of ​​the resistive screen (the surface of the resistive screen is divided into two parts: the touch area and the non-touch area, and clicking on the non-touch area is not responsive) is pressed by the display housing or the cabinet housing, which is equivalent to a certain The point has been touched. If the cabinet case is pressed against the touch area, you can increase the distance between the cabinet and the display screen. If the display case is pressed against the touch area, you can try to loosen the screws on the display case.
10. The touch screen is unstable
[Fault phenomenon]
A touch screen, its work is extremely unstable, sometimes clicks normally, sometimes it does not respond.
[Fault Analysis Processing]
In response to this phenomenon, it is important to check whether the wiring interfaces are loose, and whether the serial port and the interrupt number conflict.