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=Introduction:LCD=
 
=Introduction:LCD=
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Liquid Crystal Display(LCDs) provide a cost effective way to put a text output unit for a microcontroller. As we have seen in the previous tutorial, LEDs or 7 Segments do no have the flexibility to display informative messages.  
 
Liquid Crystal Display(LCDs) provide a cost effective way to put a text output unit for a microcontroller. As we have seen in the previous tutorial, LEDs or 7 Segments do no have the flexibility to display informative messages.  
  
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[[File:HD44780U Block diagram.png|570x250px|framed|Fig 1: LCD Block diagram]]
 
[[File:HD44780U Block diagram.png|570x250px|framed|Fig 1: LCD Block diagram]]
 
The Display Controller takes commands and data from a external microcontroller and drivers the LCD panel'''(LCDP)'''.
 
The Display Controller takes commands and data from a external microcontroller and drivers the LCD panel'''(LCDP)'''.
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[[File:LCD Animated Turn On.gif|thumbnail|Fig1: LCD_turn_on]]
  
 
Let us look at a pin diagram of a commercially available LCD like '''JHD162''' which uses a '''HD44780''' controller and then describe its operation.
 
Let us look at a pin diagram of a commercially available LCD like '''JHD162''' which uses a '''HD44780''' controller and then describe its operation.
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Revision as of 23:02, 20 December 2013


Introduction:LCD

Liquid Crystal Display(LCDs) provide a cost effective way to put a text output unit for a microcontroller. As we have seen in the previous tutorial, LEDs or 7 Segments do no have the flexibility to display informative messages.

16x2 LCD

This display has 2 lines and can display 16 characters on each line. Nonetheless, when it is interfaced with the micrcontroller, we can scroll the messages with software to display information which is more than 16 characters in length.

The LCD is a simple device to use but the internal details are complex. Most of the 16x2 LCDs use a Hitachi HD44780 or a compatible controller. Yes, a micrcontroller is present inside a Liquid crystal display as shown in figure 1.

Fig 1: LCD Block diagram

The Display Controller takes commands and data from a external microcontroller and drivers the LCD panel(LCDP).

Fig1: LCD_turn_on

Let us look at a pin diagram of a commercially available LCD like JHD162 which uses a HD44780 controller and then describe its operation.