I am receiving an ASCII string via RS232; is it possible to send that data to an N7 register directly? (i.e. ASCII String = N7:0,01)
Will a Micrologix 1500 know what to do with this or do I have to handle it another way?
No, usually you will have to read the string from the buffer(ARD,ARL), extract the number which will still be stored as a string(AEX), then convert it to an integer (ACI)
It is coming from an SMAC test unit. They can send anything I want; So I can read it into the ST register and do a string compare as well. I was just curious if there was a way to code it to go directly into a register other than the ST register.
Yes & No, They have I/O on the unit but we have used it all. So we are looking at other avenues of sending a ready signal. I think I will program a first pass to clear the ASCII string at startup and then clear it again at cycle start. That should get me what I need.
There is an ASCII to PLC Gateway from Real Time Automation that works great. It will take your string data and send it right to a string register in your Micrologix. The part is 435NBS. They have din rail or panel mounting. Very little logic is needed. http://www.rtaautomation.com/ethernetip/435nba/
They show the 435NBA for the Contrologix family. They only difference really is that the 435NBA sends data to a tag and the 435NBS will be sending to a register.
I have several customers who have successfully implemented our DeviceMaster UP products to assist with getting this ASCII data into Micrologix PLCs via Ethernet/IP. Feel free to contact me directly, and I would be happy to extend the invitation to evaluate free of charge.