Help with a LCD 4041

Jay-NC- · Post by **Jay-NC-** » Thu Jun 09, 2005 9:26 am

I have a LCD 4041 and I am having a few problems interfacing with a Allen Bradley micro logic PLC.

First I need the whole command set to make sure I am using the right commands.

I can send text to the screen with no problems at all but I can not get the display commands to work. The first one I am trying is a clear screen. I am using 254 then 88 but not sure if it is correct for the 4041.

When I send a 254 a solid square box with 3 pixels on top appears.
According to the PLC manufacture FE, 254, and \00\FE are the same in different radix's. I get the following on the display after sending the string.

Send=Displays
FE=FE
254=254
\00\FE=solid square box with 2 pixels on top with 1 pixel on top of that.

I also need the the software to program the startup screen and to configure the display, I do not have any software that even knows what display it's connected to and I have 3 different programs. screen changer, baud changer and LCD tester. There has to be something better out now.

The LCD 4041 is obsolete now, what is it's replacement?

Thank you for your help.

Miles · Post by **Miles** » Thu Jun 09, 2005 9:34 am

Hi Jay,

Thank you for posting on our forums. Is your Allen Bradley micro logic PLC communicating in TTL mode or RS232 mode? The complete manual with appropriate command set is available at the following link: http://www.matrixorbital.ca/Manuals/legacy/ This is our new support page for Matrix Orbital. I hope you fing it useful.

In regards to the replacement for the LCD4041, the part number is an LK404-55 and please see the following link for a brief part description: http://www.matrixorbital.com/product_in ... acter-lcds

Jay-NC- · Post by **Jay-NC-** » Thu Jun 09, 2005 11:09 am

It is using RS232

Miles · Post by **Miles** » Thu Jun 09, 2005 11:11 am

Can you tell me what baud rate you have it set up for??

Jay-NC- · Post by **Jay-NC-** » Thu Jun 09, 2005 11:53 am

Jay-NC- · Post by **Jay-NC-** » Thu Jun 09, 2005 12:05 pm

a 254 sends a solid square, sorry but the other pixals was rememts.

Miles · Post by **Miles** » Thu Jun 09, 2005 12:32 pm

Is the LCD4041 set up to receive 9600 baud??

Jay-NC- · Post by **Jay-NC-** » Thu Jun 09, 2005 1:44 pm

yes it is, sending text messages works perfect. Just not sure how to send the commands to clear screen etc..

If I send a \00\fe I get a solid square block. In the ascii table i have, a square block is the extended char for 254. I don't know how to make the
display see it as a pre fix to a command. If I send \00\fe and \00x i get
a square block and 88 on the screen for the two char. It should of been a clear screen command but something is not right in the way the commands are being recieved by the display.

According to the PLC manufacture, a hex fe, ascii 254, dec 254 or binary 254 are all the same value, and I agree with that but it dont work. The display should take 254 in hex, dec, or ascii. So why is the display showing the block if it was remapped to be a pre command?.

If I use the software I can clear the screen, the display is not damaged.
It has to be something in the format that is being sent.

Miles · Post by **Miles** » Thu Jun 09, 2005 2:56 pm

When you are sending a command byte to the display it must be represented by 254 decimal or FE Hex followed by the appropriate command. Are you sure the formatting is set up by your controller and your not sending straight ASCII characters??

Jay-NC- · Post by **Jay-NC-** » Thu Jun 09, 2005 4:05 pm

I set up a basic stamp to run the LCD and it works fine. With the stamp I can tell it to output ascii, dec etc.. and it works fine.

I duplicated the same problem by always outputing ascii from the stamp so this proves that the controller that I WAS tring to use allways outputs in ascii no matter what format is entered ie hex, oct, bianary or dec.

At this point it looks like the 4041 display will not work because I can not have screen control.

Can you email me the software that will work with the 4041 and its replacement?

Thank you for your help.

Bill Lovell · Post by **Bill Lovell** » Sun Sep 25, 2005 3:52 pm

I had the same problem. It was formatting.
I was using-- 1 print chr$(254):print chr$(88) NO GOOD
This worked-- 1 print chr$(254),chr$(88)
Hope this helps someone
Bill... :o