JoseM

Did the modifications to my PLC source code to just add decimal 13 at the end of my "Command String" but it still doesn't work for me. Any other ideas, thanks.

This is another output of my pc Hyper Terminal connected to the PLC. I put on my PLC code the Hex equivalent to $ which is 24 hex and also the Hex 0D for carriage return. The ASCII output which is what Hyper Terminal is presenting, you can see the ASCII for dollar-sign and nothing for 0D. Are you saying that all I need is decimal 13 and not add the $ to my string??

Thank you for the reply. I took this screen shot before I made a few changes following your suggestion on the $0D. I'm sending this string command for a purpose of troubleshooting, every 60 seconds. That's why you see about three strings registered on this Hyper terminal session. The Automation Direct technical support told me to use that carriage return in my application. The PLC I'm using is a brand that probably many are not familiar with, Toyopuc. Is this $0D an ASCII character Automation Direct has designated for the ViewMarq as the Carriage Return? I did converted the $0D to what I think is its Toyopuc Hex equivalent , 24D. Is this the correct move? Because it still not working for me.

I'm trying to get a "ViewMarq" display to respond to an ASCII string I'm sending to it via serial RS232. I connected a PC running "hyper Terminal" in place of the marquee display as I wanted to confirm that the PLC was sending the command and that the content of the command was what I was expecting. I would like to know if this ASCII string is correct and if so, why the ViewMarq doesn't respond to the message. The ViewMarq doesn't do absolutely nothing.

Thank you all for your replies. All the information provided has helped me understand almost everything I need to know I believe. I will like to ask an additional question in regards of PID instruction on CLX. I will like to see if its possible to have an HMI screen that has a field for the "Setpoint" of the PID instruction where I can adjust this number to change the level of my tank.   

I'm trying to figure out how do I go about configuring the 1794-OF4I. I read that I need to configure the output range for the output module because there are many available options. The configuration is based on a combination of four bits to tell if it is a 4-20 ma or 0-20ma, etc.

Please guys. I need help creating my first PID code in RSLogix5000. I have a tank where water comes in at the top and water comes out in the bottom with a pump. I have a pressure sensor that is used to calculate the tank water level. I have a electrical actuator that opens a butterfly valve from 0 to 90 degrees. The actuator is 0 degree = 4 ma and 90 degree = 20 ma. I'm using a 1794-OF4I analog output module to control the electrical actuator. The output module I think is set as 4ma = 0 and 20ma = 7878.