interfacing lcd

Posted on Feb 5, 2014

The EN line is called `Enable`. This control line is used to tell the LCD that you are sending it data. To send the data to the LCD, your program should make sure this line is low (0) and then set the other two control lines and/or put data on the data bus. When the other lines are completely ready, bring EN high (1) and wait for the minimum amoun

interfacing lcd
Click here to download the full size of the above Circuit.

t of time required ( about 200ns), and end by bringing it low(0) again. The RS line is the `Register Select` line. When RS is low(0), the data is to be treated as a command or special instruction (such as clear screen, position cursor, etc. ). When RS is high (1), the data being sent is text data which should be displayed on the screen. For example, to display the letter `T` on the screen you would set RS high(1). The RW line is the `Read/Write` control line. When RW is low (0), the information on the data bus is being written to the LCD. When RW is high (1), the program is effectively querying (or reading) the LCD. All commands are write commands except for 1 (`Get LCD status`), which is a read command. Thus, RW will almost always be low. The LCD can work in either 8 bit parallel mode, i. e, then entire 8 bit data can be sent at once, or it can be used in 4 bit mode. In 4 bit mode the 8 bit data is broken into packets of 4 bit data and sent (higher 4 bits first, then lower 4 bits). 4 bit mode simplifies the circuit. Before you may really use the LCD, you must initialize and configure it. This isaccomplishedby sending a number of initialization instructions to the LCD. The first instruction we send must tell the LCD we`ll be communicating with it with a 4-bit data bus (4-bit mode). We also need to select a 5x8 dot character font. These two options are selected by sending the command 20h ( `h` denotes hexadecimal format) to...

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    Auto Telephone line Recorder
    Gas analyzer circuit
    Preprogrammed single-chip microcontroller
    DOD Phasor 595
    automatic low power emergancy light
    Universal AC Motor Speed Controller Kit
    CMOS Integrated Switched-Mode Transmitters for Wireless Communication
    Morse Code circuit using ATtiny85