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    LCD interfacing with Spartan 3 FPGA

    Hello,

    I am new to FPGAs and LCD devices. I am trying to interface an LCD device with a Spartan 3 kit (LCD module - 2 line-pre connected in it). Does anyone have a basic VHDL code to display a single character / word on the LCD panel. I am finding the codes available here and on the net complicated to understand.
    Also, what is CGRAM and DDRAM in context to LCD devices. Can one read data also from the 2 line LCD devices. Are there any hex character codes for every character to be displayed on these devices.

    Thanks,
    Emma Good.

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    Re: LCD interfacing with Spartan 3 FPGA

    My suggestions:

    1.Learn to describe a MUX in VHDL.
    2.Learn to describe a D Flip Flop in VHDL.
    3 Proceed with learning the operation basics of your LCD display.
    4.Try to write: "Hello World" on your LDD with the priceless knowledge you acquired in steps 1 & 2.



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    Re: LCD interfacing with Spartan 3 FPGA

    Quote Originally Posted by shaiko View Post
    My suggestions:

    1.Learn to describe a MUX in VHDL.
    2.Learn to describe a D Flip Flop in VHDL.
    3 Proceed with learning the operation basics of your LCD display.
    4.Try to write: "Hello World" on your LDD with the priceless knowledge you acquired in steps 1 & 2.
    Thanks for the suggestions.... I already know the first two parts... still I am not able to interface an LCD.... hence I made the query....

    Anyways thanks for replying.

    Emma Good



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    Re: LCD interfacing with Spartan 3 FPGA

    Quote Originally Posted by emmagood View Post
    Hello,

    I am new to FPGAs and LCD devices. I am trying to interface an LCD device with a Spartan 3 kit (LCD module - 2 line-pre connected in it). Does anyone have a basic VHDL code to display a single character / word on the LCD panel. I am finding the codes available here and on the net complicated to understand.
    Also, what is CGRAM and DDRAM in context to LCD devices. Can one read data also from the 2 line LCD devices. Are there any hex character codes for every character to be displayed on these devices.

    Thanks,
    Emma Good.
    Check out the LCD character set in Spartan 3e datasheet. combine the upper nibble and lower nibble to represent the character in the character set. Also refer to LCD command set, and the initialization of the pins of LCD. This article may help:
    http://www.cosmiac.org/pdfs/09Tutorial6.pdf



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    Re: LCD interfacing with Spartan 3 FPGA

    What is the model of the LCD?
    Post a datasheet link please.



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    Re: LCD interfacing with Spartan 3 FPGA

    Quote Originally Posted by shaiko View Post
    What is the model of the LCD?
    Post a datasheet link please.
    http://lampex.com/Try%20Models/LCD.pdf/LM16200.pdf



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    Re: LCD interfacing with Spartan 3 FPGA

    You're display isn't a simple 7-seg LED. This display is going to need to be programmed, using a FSM to generate the correct control and data transfers to the display to program the DD RAM.

    This is a 4-bit interface 16x2 display but, it at least has a lot of detail of how to access the DD RAM etc, which might help you out.

    http://www.csus.edu/indiv/p/pangj/16...r_16x2_LCD.pdf


    Regards



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