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Do-more™ PLC: Video:
The Do-more Way Part I – The Big Picture

Video Transcript:

In this video series we’re gonna do a quick walk through of a simple Do-more controlled package sorter just so you can get a feel for how a Do-more project flows and comes together.

Given an application like this, where do we start?

Well at the end of the day, the Do-more IS just a PLC so you could just start writing Ladder code. That will work fine, but you’ll find that you have to keep going back and setting things up and configuring things and it just feels like a lot more effort that it should be.

BUT, if you have a picture in your mind of how things flow in a Do-more design and you design along with that flow, all the sudden things just fall into place and developing your project takes a lot less effort.

We call that the Do-more Way.

In this video we’ll take a few minutes to learn what the Do-more way is, and then in the following videos we’ll apply that to the box diverter design and see how much easier things flow when we do that.

When doing things the Do-more way, there are two graphics you want to keep in your minds eye.


First is the hierarchy of the Do-more configuration. You always want to start with the CPU configuration because everything below it can be affected by which options you turn on in the CPU. For example, if I enable the Ethernet I/O master, it add another I/O item to the I/O Configuration. And if I turn it off, it goes away.

Next you want to configure all the I/O that’s local I/O and Remote I/O. Why? Because it can affect all of these guys below it.

Likewise, Module configuration can affect all of these, and Device Configuration can affect all of these, etc. You get the idea. Any item in this list can affect any item beneath it. So it makes sense to start at the top and work your way down. If you do that, then all of the sudden things will just start falling into place. Do you have to do it in that order? No, not at all - but you will find your doing a lot of jumping around and back peddling and things will seem to be a lot harder than they should.

And the good news is you don’t even have to remember this chart – when you bring up the system configuration - look – it’s in the exact same order – isn’t it? Just start at the top and work your way down to configure the system quickly and easily.

The second thing to keep in mind is that everything in the Do-more revolves around Devices. What’s a device? You might think it’s anything you want the Do-more to talk to like a simple I/O module, a VFD, an encoder, a remote rack, an EtherNet/IP device, etc. But that’s not quite right.

In a Do-more project, a “Device” is a little chunk of code that sits between your ladder program and the hardware you want to talk to. You simply configure the Device – this little chunk of code - and it handles all the low level nasty details for you. The com protocols, handshaking, memory allocation, etc.

You don’t have to worry about any of that, which is one of the things that makes programming with the Do-more so easy.

For example, If we need to use the serial port on the CPU, we just tell the Do-more how we want that serial port to behave by selecting one of these options, like a general purpose serial port for example. Then when we configure it, the Do-more only presents us only with the options that are needed for a general purpose serial port. If we want to use it as a Modbus RTU client port, then we have a few more things we need to configure.

And that’s a key point – the Do-more creates all the devices for you. You just tell it how you want to use the device, and configure the appropriate options which the Do-more exposes for you.

And the cool thing about that is you can’t configure the wrong parameter – since the Do-more only exposes the configuration parameters you need, you don’t have to worry about configuring the wrong parameter. The Do-more won’t let you mess up.

So the key take away here is the Do-more is Device Centric. EVERYTHING revolves around creating and configuring these devices.

You can think of it like this.

Here’s the device. The Device handles the care and feeding of the hardware.

An instruction can only talk to a device – it can’t directly manipulate the hardware. Which is awesome, because the device knows how to handle the hardware, how to feed it, how to allocate memory for it, how to handle issues, how to respond to handshaking, how to set status flags, etc. It takes all of that hassle off of your back - you don’t have to worry about any of it.

An Instruction can also talk directly to memory, like when doing math. The instruction takes data out of memory, does something to it and then puts it back in memory, for example.

A Device can talk directly to memory – maybe data is coming in that serial port, the serial port device puts that data directly into memory or pulls data from memory to send back out all behind the scenes – you never have to worry about it. The device just takes care of it, sets the appropriate status flags, manages the buffers, et.

We call this being Device Centric. Everything revolves around the device.

Now as a side note a server is just another device – in that it talks directly to the hardware, but since it just runs in the background moving data between memory and the hardware – like Modbus TCP data for example - we draw that as a separate device off to the side like this showing that most of the time it doesn’t need any ladder code to function. There are always exceptions, of course, but for all practical purposes, this is a good representation that reminds us that servers are devices that are there, but we never really see them or deal with them directly.

And that’s it. If you can remember to configure the Do-more from the top down and that the Do-more is Device Centric, your programming will flow much more effortlessly, your life will be lot easier, and you will be more productive.
In the next video, we’ll show you how easy everything gets when you put these two concepts work as we develop that simple box diverter example.
If you have any questions, please call AutomationDirect’s free award winning tech support during regular business hours. They will be happy to help. And don’t forget the forums. There are lots of folks there that love to share their years of experience. Just don’t post any questions directed at AutomationDirect’s Support staff there – they don’t monitor the forums on a regular basis.

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