An LCD (Liquid crystal display) is

An LCD (Liquid crystal display) is a low-cost, low-power device capable of
displaying text and images. LCDs are extremely common in embedded systems, since such systems often do not have video monitors standard for desktop systems. LCDs can be found in numerous common devices like watches, fax and copy machines, and calculators .The basic principle of one type of LCD (reflective) works as follows. First, incoming light passes through a polarizing plate. Next, that polarized light encounters liquid crystal material. If we excite a region of this material, we cause the material’s molecules to align, which in turn causes the polarized light to pass through the material . Other wise, the light does not pass through. Finally, light that has passed through hits a mirror and reflects back, so the excited region appears to light up. Another type of LCD(absorption) works similarly, but uses a black surface instead of a mirror. The surface below the excited region absorbs light, thus appearing darker than the other regions . One of the simplest LCDs is 7- segment LCD. Each of the 7 segments can be activated to display any digit character or one of several letters and symbols. Such an LCD may have 7 inputs, each corresponding to a segment, or it may have only 4 inputs tore present the numbers 0 through 9. An LCD driver converts these inputs to the electrical signals necessary to excite the appropriate LCD segments. A dot-matrix LCD consists of a matrix of dots that can display alphanumeric characters (letters and digits) as well as other symbols. A common dot-matrix LCD has 5columns and 8 rows of dots for one character. An LCD driver converts input data into the appropriate electrical signals necessary to excite the appropriate LCD bits . Each type of LCD may be able to display multiple characters. In addition, each character may be displayed in normal or inverted fashion. The LCD may permit a character to be blinking (cycling through normal and inverted display) or may permit display of a cursor (such as a blinking underscore) indicating the "current" character. Thisfunctionality would be difficult for us to implement using software. Thus, we use an LCDcontroller to provide us with a simple interface, perhaps 8 data inputs and one enable input. To send a byte to the LCD, we provide a value to the 8 inputs and pulse the enable . This byte may be a control word, which instructs the LCD controller to initialize the LCD, clear the display, select the position of the cursor, brighten the display, and so on . Alternatively, this byte may be a data word, such as an ASCII character, instructing the LCD to display the character at the currently-selected display position

Kết quả (Việt) 1:

Một màn hình LCD (Liquid crystal display) là một chi phí thấp, năng lượng thấp thiết bị có khả năngdisplaying text and images. LCDs are extremely common in embedded systems, since such systems often do not have video monitors standard for desktop systems. LCDs can be found in numerous common devices like watches, fax and copy machines, and calculators .The basic principle of one type of LCD (reflective) works as follows. First, incoming light passes through a polarizing plate. Next, that polarized light encounters liquid crystal material. If we excite a region of this material, we cause the material’s molecules to align, which in turn causes the polarized light to pass through the material . Other wise, the light does not pass through. Finally, light that has passed through hits a mirror and reflects back, so the excited region appears to light up. Another type of LCD(absorption) works similarly, but uses a black surface instead of a mirror. The surface below the excited region absorbs light, thus appearing darker than the other regions . One of the simplest LCDs is 7- segment LCD. Each of the 7 segments can be activated to display any digit character or one of several letters and symbols. Such an LCD may have 7 inputs, each corresponding to a segment, or it may have only 4 inputs tore present the numbers 0 through 9. An LCD driver converts these inputs to the electrical signals necessary to excite the appropriate LCD segments. A dot-matrix LCD consists of a matrix of dots that can display alphanumeric characters (letters and digits) as well as other symbols. A common dot-matrix LCD has 5columns and 8 rows of dots for one character. An LCD driver converts input data into the appropriate electrical signals necessary to excite the appropriate LCD bits . Each type of LCD may be able to display multiple characters. In addition, each character may be displayed in normal or inverted fashion. The LCD may permit a character to be blinking (cycling through normal and inverted display) or may permit display of a cursor (such as a blinking underscore) indicating the "current" character. Thisfunctionality would be difficult for us to implement using software. Thus, we use an LCDcontroller to provide us with a simple interface, perhaps 8 data inputs and one enable input. To send a byte to the LCD, we provide a value to the 8 inputs and pulse the enable . This byte may be a control word, which instructs the LCD controller to initialize the LCD, clear the display, select the position of the cursor, brighten the display, and so on . Alternatively, this byte may be a data word, such as an ASCII character, instructing the LCD to display the character at the currently-selected display position