Labview control LCD by PC parallel port

[aludlak]

Hi, everyone! I newbie and I have a project, control LCD 16x2 thought parallel port. I written a program (not yet wirtten control RS,RW and E). Would you please see, it wrong or right? And could help me complete it or Who could sent me a code about that (my email: nvt_lab2004@yahoo.com). .
 my hardware conection: 2-9 pin(of parallel 25 pin) conect with D0 - D7 (of LCD), RW pin as GND. 14, 16 pin of parallel port conect RS and E of LCD. Please help me. Thanks you. Funny!

This links my program:
http://www.yourfilehost.com/media.php?cat=...file=LCDLPT.rar

[Mathan]

Hai,

Please attach the program directly here and don't give link to any external websites. This will attract more people to look in to your code and help you.

Use Add Attachments located below the compose box. Thanks for your understanding,

Mathan

[Coq_Rouge]

Hi

First of all my eyes are burning. You should work with your front panel color. Most people do not wear shades indoor . Using the Parallel Port in LabVIEW for output is easy. You may use VISA. Doing it for input is not so easy but doable indeed. You find more if you search the NI site for parallel port.  Also pay attention to details those small red dots in the block diagram is a warning. Also this is important "Using the parallel port for digital output is really rather trivial if working with the Windows API. The main trick is to tie pins 11(Busy) and 12 (Paper Error) to ground"

Here is a useful link

http://digital.ni.com/public.nsf/allkb/B937AC4D8664E37886257206000551CB

By the way in this document the pictures is missing can someone in NI fix this

This link has pictures http://www.physics.utah.edu/~jui/3620-6620/labs/Using_the_Parallel_Port_in_LabVIEW.pdf

[Ben]

[Warning!]

The parallel port on the PC is designed as an interface and is not capable of diriving heavy loads.

Please ensure your circuitry does not load the parallel port.

Failure to do so could result in a damged port, moterboard or worse!*

[End of Warning]

Ben 

*After that it become even harder to get it working. 

[aludlak]

Thanks everyone Replyed!

@Mathan: I attached direct it . Please help me.

@Cop ruege: I like that color in front panel. I'm beginer, only see about in port and out port and feel inport.vi and outport easy. I'll see VISA following you said. But I don't have more time for this project.

@Ben: Thanks for your waring. But it's a component in my project. I have to do comunication in LabVIEW with Parallel and COM port. I  do not yet comunication about COM port. Now I have to  Labview control LCD 16x2 by PC parallel port. I don't have more time.

Could who please help me. sr cause my E not good, but i think everyone understand i say: Funnysmileywink:

[Coq_Rouge]

First of all VISA is very simple to use. It could save you for a lot of work.

Se here http://zone.ni.com/devzone/cda/epd/p/id/4213 and here http://digital.ni.com/public.nsf/allkb/81265FE73475F18B852563B60079D249. Your current VI do not make much sense to me right now

[Dennis_Knutson]

Why would you mark your response as the 'Accepted Solution'? Do you not want any more help? If you do, you should change it. Go to Options and modify it.

[Dennis_Knutson]

You also need to provide some critical information. You have not provided the make and model of the LCD or the data sheet. We have no idea how the lcd is supposed to work. We have no idea how you have wired the parallel port to the lcd. Also, the interploation function you have does not make much sense. What are you attempting here? With just an 'a' as an input, you are writing ox61 twice with the Outport.

[aludlak]

Thanks Cop rouge and Dennis Knutson!

I've learned Labview for a month. I know my program can't run cause it wasn't written for RS, RW, E of LCD. I don't know how control it with in port.vi and out port.vi in labview. I can't find any supports of Labview for LCD as in C, Bascom .... really I have to change idea in my program. Could you please advise me a idea about use parallel port to control LCD.

I attached circuit, datasheet of LCD.

Thanks you.

[Dennis_Knutson]

Here's something quick and dirty. Since there are separate registers for the parallel port and you have wired the data register to the data inputs of the lcd and 2 of the control register pins for the E and RS, it made things a bit simpler.

I did not do anything about the instruction data to set the lcd into the mode you want. You can modify the data write VI and change the RS level to 0.