hepworth07

My 1st and 2nd AWA append characters are set to \d and \ff In real term, for the number 150 the string looks like: hex mode - 3135300d hex & ASCII - 131 535 030 0d I have been in touch with the manufacturer on the settings for the display, I told them the hex mode string and they advised me on the settings for the display. So I believe the settings for the display and ASCII string match. Because I can see the ASCII string coming from the PLC in real term, I believe the PLC program is fine. The only thing left I am unsure about is the pinout of the channel 0 port and how I have wired the PLC and display together. I'm fairly confident that I don't need to do anything with RTS, CTS or DCD. based on my settings. The manufacturer has tested my specific display and got it working, using (TxD) to terminal 3 RXD and (signal GND) to terminal 2 Comm. Therefore If I use pin 7(TxD) to terminal 3 RXD and pin 2(GND) to terminal 2 Comm. from the above pinout, then I can't think of any reason why the display wouldn't work. However, I'm 99% sure I tried this before I sent the display away to be checked. DF1 and ASCII mode are both RS232 aren't they?

Right I'll put the PLC in ASCII mode. Although, I was getting ASCII strings to display in realterm with the port in DF1 mode, using an AWA instruction.

The manufacturer connects TxD to RxD (display terminal 3) and signal common to signal common (display terminal 2). This allows them to control the display via real term on there pc. They don't need the demand or TxD terminals connected to anything. However, does the PLC need the RTS and DTS connected to know to send the signal? If I were to connect the PLC's RTS and DTS to each other, could I get around this? Also, would DF1 Full duplex be the correct setting for channel 0? bearing in mind it's a master slave connection. I read somewhere that you had to be in DF1 full duplex to use an AWA and AWT instruction?

Thankyou for the reply. The settings mentioned above are all changeable on the display, so I've configured them to the settings of the PLC, including setting the baud rate to 19200 etc... I have contacted the manufacturer and told them my PLC settings and what my ASCII string is (31 32 33 0d) They then advised me on the settings of the display. Because it still wasn't working I sent the display back to the manufacturer, who have got the display to work when they connected it to a pc via real term. using the same ASCII string as mine. Based on my interpretation of the manual and the manufacturer saying the wiring they used to get it working is "Data common to terminal 2, data to terminal 3" I would say it is a DCE device? I have recently had it pointed out that the wiring diagram from london is for connecting two displays together (my bad) however I have tried connecting both RXD and TXD to the displays RXD pin, to no avail.

Hello all, I have a micrologix 1200 series C PLC (L24 - BXB) I have created a program that outputs an ASCII string via channel 0. I am sending (123 is an example, the number varies in the program) 123<CR> at 19200 baud, 8n1 using RS232, 31 32 33 0d in Hex. I can get this data to appear in both real term and hercules, when I connect the PLC to my PC in run mode. however, I cannot get it (or anything) to appear on my serial slave display. London Electronics INT2-S2-0-0-0-RDLV-DC-0 http://www.london-electronics.com/manuals/INT2S_F21.pdf I have sent the display back to the manufacturer, who have confirmed it is working and are going to send it back shortly. The manufacturer has told me the settings for the display based on my ASCII string and com port settings. The only thing I can think of is the wiring connection. It is currently wired as shown in the picture below, titled application note (RS232) I am using a 1761-CBL-AM00 cable, with one end cut off to connect the cut cables to the screw terminals. based on the 8 pin mini din pinout from this picture Is that drawing accurate? or is it something like I have to connect the RTS to the CTS etc... Channel 0 port settings attached below. The instruction I am using is an AWA, again I have got the ASCII string to display in real term and hercules. The program file is attached below, if it helps. Any help would be brilliant before I pull all of my hair out Thanks James UNTITLED_BAK008.RSS

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}

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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