Updated: Aug 29, 2020
Welcome back to another unlikely techie blog post. This time around, I will try to explain I/O (input/output) connectivity. Remember the last blog post about communication protocols? Connectivity and communication are key!
There is a vast range of I/O connectivity options which are needed to perform real-time simulation and testing. There are digital, analog, shared memory, fault insertion, PWM, encoders, and resistors, and many more options, depending entirely on your application. The question I asked myself while writing this post was: Is there a possibility for a non-techie to figure out what type of I/O connectivity was chosen for a specific application?
Is This Digital?
Unfortunately, this is not exactly how engineers look at I/O connectivity (definitively not their scope at least). Or to answer my question in plain and simple English: no. I/O connectivity can be be characterized as a short distance and point-to-point communication between two parts that need to be connected. It connects the sensors and actuators to the computer (or to stay within unlikely-techie-language the plant or whatever peripherals there might be).
For instance, a digital input detects if a voltage is above or below a given threshold, therefore allowing controllers to detect logic states (high/set/1), whereas the output can send the logic state out (an output can also be instructed to be low, meaning it is connected to ground, which means it doesn't produce voltage). If you look at analog I/O it's a completely different way of measurement: sensors measure signals from their surroundings (mostly natural factors such as temperature, flow rate, and pressure, among others), which then have to be translated into digital signals in order for the computer to be able to read them. It's because of that translation part, that engineers use an analog I/O interface (btw. most control actuators move on the authority of analog signals).
But How Do Communication & Connectivity fit together?
I want to finish this blog post off by pointing out, how communication protocols and I/O connectivity work together. The reason behind this is, that at some point I got a little confused: How do communication protocols and I/O connectivity fit together. And since I have a lot of experts all around me at my job, I ventured out to find an understandable explanation. So here it goes: I/O connectivity is the technical enabler of communication protocols. You need the information flow established technically, in order for protocols to control the information and look at it closely (e.g. from a security aspect).
Next time we'll look at a story I recently covered (and I am super excited to share it with you!). We will discuss plasma physics and the future of energy!
Stay curious! And in case my explanation didn't fully make sense to you, here are some additional links for you to look at: