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hepworth07

RS-232 micrologix 1200 communication

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Hi all, new user. New to PLC's aswell. I am struggling to programme a Micrologix 1200 series C (L24BXB) to communicate with a serial slave display via channel 0. http://www.london-electronics.com/manuals/INT2S_F21.pdf The serial slave display Accepts RS232 in ASCII format. Addressable 00 to FF. Able to extract data from complex strings. 300, 600, 1200, 2400, 9600 baud rate. I am using RSLogix Micro Developer version 9.00.00 The programme counts an incremental encoder's pulses via the HSC, maths is performed on the pulse count, the final value is found in N7:0 on rung 20. Everything before rung 21 works fine. I'm trying to get the serial slave display to show the value found in N7:0. This is where it goes wrong, I have tried multiple ways to create the programme and multiple ways of configuring channel 0. The display hasn't changed at all. Please could someone view the program and tell me where I am going wrong? UNTITLED_BAK008.RSS

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First, make sure your version of the display has the RS232 option, that's what the MLX has. Next, find a good serial port terminal emulator. I use Hercules SETUP Utility. Hook the display up to your computer (you may need to get a USB-serial adapter) and send strings to the display until you figure out what settings (baud, parity, etc.) and protocols (what characters to send) work for your needs. You might need to send more that just the number you want to display. Once you have that figured out, program the MLX to those settings. Then, hook your computer up tot he MLX, and make sure that what is being sent is what you're expecting. Final step is to hook the two pieces together.

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Thank you, that Hercules software is brilliant. I've used it to confirm the MLX is outputting the correct ascii code. However the display doesn't change when I send strings to it via Hercules, after trying multiple settings and characters. I have been in touch with the display manufacturer, they are going to email me the correct display settings to use based on my MLX settings and ascii code. If that doesn't sort it, the only thing left that I can think of is that the display is malfunctioning. This has been driving me mad for the last few days, its a massive relief to know the MLX and software are fine. Thanks again. P.S. The display is the RS232 option. The hex code being communicated is the hex variable followed by {0D}. Eg. The number 150 is sent as {31}{35}{30}{0D} Edited by hepworth07

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Hi, hepworth07.

Have you ever tried to extract text from pdf files? Do you have any 3rd party toolikts recommended? Any suggestion will be appreciated. Thanks in advance.   

 

 

 

Best regards,

Pan

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