Today’s post covers ASCII, string manipulation and how to deal with readable text in a PLC. The picture above is from a ControlLogix program (Allen-Bradley, RSLogix5000 v.16) I wrote back in 2006. The program communicated with a PC-based Cognex machine …
Today’s post is in response to an e-mail I received asking for my thoughts on Tag Structure. In part, George Steel wrote: Great site, thanks for all your efforts. I am working on positioning my org to move from RS500 …
A one shot, or “differential”, is used to develop a signal that is exactly one scan in duration. As shown in the diagram above, when a signal is applied to a contact (a Pushbutton in the diagram above), no matter …
Computers hate decimal. I mean, just because we have ten fingers and ten toes, we think we can dictate what base other computing entities should think in. Well, it’s really quite inefficient when you think about it, its so easy …
I mentioned last week that I am working on what I believe is the first truly advanced non-platform-specific book on PLC Programming. My friend Tony over on Factory Automation Software Blog has reviewed some books that come the closest, but …
In last weeks’ post, I discussed acquiring data using a PLC to capture values from an analog card. I showed some fairly straightforward methods of capturing data using FIFO methods, averaging data values, and how some of the ladder logic …
Ladder Logic 402: Data Manipulation and Filtering Read more →
Todays post is in response to a request by Quy Phan, who I met a couple of weeks ago while teaching for Automation Training in San Diego. He is having some problems with some existing equipment concerning noise on his …
In my last post on PLC Memory Organization, I mentioned that I had not really covered how scanning actually works in a programmable controller. This is certainly a topic that needs to be discussed for an understanding of PLC programming, …
One of the first decisions that needs to be made when designing a PLC system is memory allocation and organization. In the early years of the PLC memory came at a premium… 1K (one kilobyte) of memory for the program …
I would like to make myself available to any company or group, worldwide, that desires truly advanced training in industrial automation-related fields.
