View Full Version : Micrologix 1100 LCD programming trouble

July 17th, 2009, 10:26 AM
Has anyone had success programming the LCD screen on the 1100? I've been working with this for awhile and have discovered that if you're on a screen set up for data entry, you sometimes have to press the ESC or OK buttons twice before it will allow you to exit the screen. This causes problems if you're using an integer register to track which screen you're on, because the register will index at the first button press but the data input screen will remain shown (even if another LCD instruction has executed) until the button is pressed again. When it finally exits the data entry screen, it sometimes skips over the intended screen due to the extra button presses. I've tried all kinds of kludge logic (timers, counters, intermediate screens) but can't find anything that works consistently.

The funny thing is that this problem is not addressed in Rockwell's white paper 1763-WP001 (http://literature.rockwellautomation.com/idc/groups/literature/documents/wp/1763-wp001_-en-e.pdf) on the subject. The examples they provide that use data entry screens do not work the way they are written because of this problem. Either the author didn't test his logic, or I'm missing something. (I'm using a Series A PLC.)

July 17th, 2009, 10:43 AM

I too have seen some of the "glitches" that you have experienced as well, with my first integration with the 1100 about 3 years ago.
I was able to follow the examples supplied in the white papers with no difficulty.
I am wondering if the white papers changed or something.
I will take a look at the program that I developed and check for validity. As far as I remember, the LCD display from my perspective is good for the most simple changes..
If I had to do it again, I would have just used a PV300 instead.
It was very cumbersome as I remember, and the operators had to open the electrical cabinet in order to make the necessary changes....which is a no-no in my industry.
Re-Check your logic.
Are you using a new SR for your HMI logic?

July 17th, 2009, 11:46 AM
SNK, thanks for your reply.

I'm using the PLC as a programmable cam switch with an encoder, and the LCD will be used for adjustment of the on/off positions (very rarely, and by electricians only). Any more usage would certainly justify a separate HMI.

Concerning the white paper, I programmed Example 10 (p. 28) exactly as it is shown. But when the "modify" screen is shown, I have to press ESC twice to exit and it ends up skipping over screen 0 and ends up on 1. This is the same behavior I get with my program.

I would appreciate it if you could let me know how you implemented the 1100 data entry on your past projects, or perhaps post your RSS file.

By SR, do you mean subroutine? Right now everything is in the main routine but I might create a separate ladder for the HMI logic eventually.

July 17th, 2009, 12:52 PM
By SR I meant new Subroutine.
I don't like having everything in one MAIN block.
I do remember even with the most basic application having difficulty with the ESC button.
I will post some basic logic that I used for screen control.

July 17th, 2009, 04:22 PM
OK, if you know that your Reject program works correctly, then I must be doing something wrong. I downloaded your program to my 1100 without making any changes. From the main screen, once I hit ESC or OK to go into the delay time adjust screens, I can't get out of them. Pressing ESC has no effect the first time; the second press takes me back to the main screen but it immediately switches to the data entry screen again (due to the second ESC trigger). This is exactly the behavior I am seeing with my program as well. Any thoughts?

September 21st, 2009, 08:44 PM
Hi kolyur

I have been working with micrologix 1100 about 6 months, and I read in Publication 1763-RM001B-EN-P - April 2007 that if you are using the display as input, and if you press the ESC button the controller cancel the input but the line 2 and 3 are not updated, for this reason when you press twice you notice that it comes to the first screen