Virtex-4 ML403 16x2 LCD

Started by Shela December 5, 2006
HI all,

I am a student. I am new to verilog and FPGA.
I have a question.

How do I use the 16x2 LCD which is on the development board?
I have a verilog code which I want the LCD to load the ASCII char from
the verilog code I written. The verilog code is just a few shift
register acting like a LUT (look up table).

Is there any way i can control the 16x2 LCD or is there any macro?

I realize that the LCD i/o is connected to the GPIO so is there any way
i can use the on board LCD?

Thanks in advance.

Regards,
Shela

Shela wrote:
> I realize that the LCD i/o is connected to the GPIO so is there any way > i can use the on board LCD?
Yes, but it requires some work. There is a controller chip on the LCD. I don't know which one it is on the ML403, but most of the time it's something like the HD44780 (just google for the datasheet). You'll have to look in the ML403 User Guide, the kind of LCD controller should be mentioned there. After power-up, you have to initialize the LCD first. The neccessary initialization sequence is shown in the datasheet. Basically that means you have to toggle the IOs that connect to the LCD in a specific way with specific pauses in between, i.e. you need a little state machine that performs the startup sequence. After that you again need to send a specific sequence for every character you want to display (i.e. send a "print charcter"-command to the LCD). The alternative is to do it in software, e.g. include a PowerPC or MicroBlaze in the design and write a C-program to do it. There are probably example designs for the ML403 that do this. cu, Sean -- My email address is only valid until the end of the month. Go figure what the address is going to be after that...