Stop the Presses

STOP THE PRESSES! Major advancement in automation technology is upon us…Rockwellis introducing a Micrologix processor with USB.

Can you believe it? Isn’t it everything you and I have been waiting for with “baited” (whatever that is) breath?

Why next week we might hear that apples are coming to market with another shade of red; TVs with digital tuning and cars with radial tires.

I mean, really, I don’t mind USB. I just don’t think it has much place on the factory floor. Let me explain.

1.       It has no legs – 16feet is about it. You have to be really close to the equipment to get connected. Why do I want to walk halfway across my plant to plug my laptop into this processor? Why can’t I access it from my desk.

2.       There are a number of different standards. One side is, of course, the controller side and the other is the adapter. You have to make sure that you’re the end that your customer needs you to be. And there’s a bunch of different standards. USB 1.0, 2.0 and 3.0. Some of them incompatible depending on the implementation. It’s really not as simple as the Marketing guy saying “we need to support USB” and you doing it.

3.       And then there are power considerations. These USB devices will want power and you have to support it. How much? Well, it varies…

Lots of ways to screw up with USB. That’s one of the reasons I don’t like it.

But I understand why they are doing it. PCs don’t have serial ports anymore. In the effort to get the price of a PC to less than a candy bar, they’ve eliminated the serial port and most everything else. I’m sure over the last 5 years they have had a host of customers asking for USB. And now, they’ve “quickly” responded.


The trend now is to smart phones, IPADs and a host of other wireless devices. They should have just skipped right past USB and made their controllers work seamlessly with these devices. You can bet that in the bowels of Mayfield Heights they are right now thinking about writing specifications for wireless access to those controllers. [I am sure I’m being a bit unfair here – it takes a long time to get anything done in any huge corporation]

OK, here’s what really frosts my cookies about this. Lots and lots of their customers are going to be confused by this. They’re going to think that RA has just introduced some magic way to access PLCs. That the USB port is the magic bullet for uploading and downloading programs and doing data table read and writes.

Believe me it won’t be. It’s going to be the same as a serial port.

On the serial ports, you need a DF/1 protocol to send PCCC messages. And with those messages you can read or write any data item in the controller.

Now those PCCC messages are going to have to be sent over USB. So all the programs that used a serial port before, can switch to a USB port, remove the DF/1 (I’m betting) and send the same messages as they sent before.

This is going to be just another minor improvement in their product lines. Nothing like a major advancement that I’m hearing from some customers.