DeviceNet PC Interface Options

There is a lot of discussion going on now about the evolution of the PC market. I remember years back (sounds like I’m getting old) when the first PCs came out. They had these single length ISA slots and then incredibly long double-length ISA card slots. We use to buy cards for those things all the time.

At that time it was common that you bought a video card and had to plug it into one of those slots. That was before anyone had video circuitry right on there motherboard. So part of the fun of the assembly process was to install these ISA cards. It was maddening. They were sometimes hard to install because the end of the card with the DB15 on it had to fit in the slot on the external part of the PC. It gives me the shudders to think about it. If the computer was shaken a bit and things didn’t work you’d not only reboot it but you went and unplugged and re-plugged all these cards. I feel like Fred Flintstone telling you about it.

During the ISA card era DeviceNet ISA cards started showing up. These actually worked pretty well except that they were dang expensive (even today’s still are). These guys usually had two DeviceNet ports and had direct access to the PC over the ISA bus. People could write programs for Windows that would talk to the card and transfer data over the network.

Needless to say the ISA card era died when bus speeds increased so much that the ISA technology was obsolete. Walla – here’s PCI. PCI stood for Peripheral Component Interface. There was a very expensive chip set that you could use to create PCI cards. At least now the cards weren’t a foot long. Everything had kind of shrunk in a PC and the interface cards were no exception. Now they were only 5 or 6 inches long. Now companies not only made DeviceNet cards, you could get ControlNet cards, Profibus cards and a whole lot of other ones. So people retooled their application to use the new PCI cards and off they went.

Well here we go again… Now PCI is getting obsolete. PC manufacturers are loading the motherboards with everything they can eliminating the need for PCI’s. There’s no need for fancy video drivers or serial port cards. It’s just extra real estate and extra expense.

But that presents a real problem for the people using the PCI interface cards for networking. Now they have to retool their applications for USB. Now high speed USB (Rev 2.0) is pretty fast but it’s no where near as fast as a bus interface like PCI. Some applications that really took advantage of that are just going to be out of luck in a few years.

I happened to call Dell today. They tell me that they now have only 2 tower boxes that have PCI slots and can’t say for sure that they’ll have any in 2010. So, if you are one of the lucky ones that got to retool your application twice already your in luck, you’ll get to do it again. This time for USB.

Better stop depending on the PCI card today. It’s going the way of the serial port meaning missing in action. Luckily RTA will have some nifty USB products in the future to save your <you know what>. Keep watching. Same Bat Channel. Same Bat Station.