56. Where is the use of GPRS technology for display screen?
In the GPRS data network based on mobile communication, the data of our LED display is communicated through GPRS transceiver module, which can realize the small amount of data transmission from point to point in remote places and achieve the purpose of remote control.
57. What is a USB interface
The English abbreviation of USB is a UNIVERSAL SERIAL BUS, which is translated into Chinese as Universal Serial Bus. Also known as Universal Serial Interface, it can support hot plug-in and connect up to 127 PC peripherals: USB 1.0 and USB 2.0.
58. What is a Metal Framework
The indoor LED screen is generally made of aluminium alloy, which is equipped with the drive board, lamp board, control circuit board, display board and switching power supply. The outer frame is made of aluminium alloy frame for LED display, aluminium alloy clad stainless steel, sheet metal integration, etc. The outdoor screen frame is generally made of angle steel or I-beam steel according to the size and load-bearing capacity of the screen body. The outer frame can be decorated with aluminium-plastic plate, stainless steel and other materials.
59. What is out of control? How many kinds?
The out-of-control points can be divided into three categories: blind spot (also known as dead spot), constant bright spot (or dark spot) flash point.
60. What is the out-of-control pixel rate of LED display?
Out-of-control pixel rate is the percentage of out-of-control pixels on the whole screen to the whole screen. There are out-of-control pixels in the LED display screen (illumination status does not match the display status required by the control requirements, such as blind spots). But as long as the out-of-control pixel rate does not exceed the allowable range and is distributed discretely, it is normal. According to the industry standard "General Specification for LED Display Screen", the out-of-control pixel rate of the outdoor screen does not exceed two thousandths, and the out-of-control pixel rate of the indoor screen LED display wall does not exceed three thousandths.
61. What is three in one? What are its advantages and disadvantages?
It means that SMT lamps encapsulated with three different colours of RGB LED wafers are vertically juxtaposed according to certain spacing, which not only has the advantages of three in one but also solves the disadvantages of three in one: complex process and difficult maintenance.
62. What is RS-232 communication, RS-485 communication and RS-422 communication? What are its advantages?
RS-232 is a serial data interface standard. The basic communication mechanism of RS485 and RS232 is the same. Its advantage is to make up for the shortcomings of RS232, which cannot manage multiple devices simultaneously. The communication principle of RS-422 is similar to that of RS485. The difference is that its bus is two pairs of twisted pairs (four wires) labelled R+R-T+T-.
The disadvantage is that the wiring cost is high and it is easy to make mistakes. It's less used now, so I won't go into details here.
Quick Link to LED Display Wall Elementary Knowledge Products and home page