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EXPO MUSINGS

by Tom Cantrell

Start • Bye-Bye VME, Hello PC • Build a Better Box • Wire Fires • I Want My PCTV • Sources 

BYE-BYE VME, HELLO PC

Because few have the audacity to come right out and admit that VME is dead, I will. Now, now, hold off on the flame mails. Of course, VME will keep selling into existing accounts. After all, industrial applications have long life cycles.

What I mean is that embedded PC, in all its flavors (especially CompactPCI) is inexorably squeezing VME into an ever-narrower and less-sustainable niche. Although it’s argued that VME has technical advantages (more slots!), that won’t prove compelling in the face of the Wintel juggernaut. Heck, even the SBC Group at Motorola, the company that drove the creation of VME in the first place, is pushing CompactPCI.

But who wants to run funky PC software in hard-core embedded apps? Well, if you don’t, there’s Linux and plenty of RTOSs that run on EPCs. And, with no shortage of packaging and bus options, EPCs cover a spectrum of size and performance that easily outflanks VME.

(Click here for figure)

Figure 1—This baby board from Cell Computing offers pretty much everything from soup to nuts. They piled lots of goodies onto a 333-MHz PII including a 256-KB L2 cache, NeoMagic graphics controller with 2.5-MB VRAM, Phoenix BIOS, SMC Super I/O chip, and up to 256-MB EDO or SDRAM.

For instance, Cell Computing offers what looks in Figure 1 like a typical $400 333-MHz PII motherboard—the only difference being that this micromotherboard is a mere 3" x 5" (see Photo 1)!

Photo 1—The top and bottom views of the 3" ý 5" Cell Computing micromotherboard reveal clever packaging and a tight layout.

For quick development, Cell Computing offers a $349 Slot Card that the micromotherboard plugs into. This little gem includes all the usual connectors (CRT, parallel, two serial, IDE, FDD, keyboard, and mouse), an LCD interface, CompactFlash slot, and three full-size PCI slots (see Photo 2).

Photo 2—The Cell Computing Slot Card provides easy connection to the micromotherboard and offers I/O expansion, such as the cute IBM 340-MB hard drive that fits in the Compact Flash slot.

If you flip the Slot Card over, you’ll find a socket for the new M-Systems Millennium DiskOnChip flash disk that packs up to 8 MB in a standard 32-pin DIP (see Photo 3).

Photo 3—The M-Systems Millennium DiskOnChip looks like a disk to software, but it offers the features of silicon: small size, low power, and high reliability.

With complete hard-disk emulation, no-glue hardware interface, and a footprint-compatible growth path to 144 MB (via the DiskOnChip 2000 module), these puppies are finding their way into more and more designs, a notable example being the latest generation of set-top boxes from WebTV.

For typical blue-collar EPC apps, the good old ISA bus lives on, despite the hand-wringing that its stubborn refusal to make a graceful exit causes Wintel execs. Nevertheless, just because it has a nearly 20-year-old 8-bit bus doesn’t mean that the Teknor VIPer830, pictured in Photo 4, can’t keep up with the new kids.

Photo 4—Teknor’s VIPer830 is not only a complete 433-MHz Celeron PC with up to 128-MB SDRAM and 10/100Base-Tx Ethernet on a half-size ISA board, but it also includes a PC/104-plus connector for an extra I/O board.

The true performance-at-any-price customers, who were formerly the mainstay of VME, may see the light in the aptly named Judgment Day CPU board from General Micro Systems (see Photo 5).

Is this an ironic indicator of which way the wind is blowing? If you want to find out more about this CompactPCI hot rod, click on over to General Micro Systems at www.gms4vme.com.

Photo 5—Judgment Day, a CPU board from General Micro Systems, has lots of punch—dual 550-MHz PIII CPUs, 512-KB L2 cache for each, up to 1-GB SDRAM, 10/100Base-Tx Ethernet, ultrawide SCSI, AGP, the usual I/O, and a mucho-macho heat sink. Where’s the Judgment? Is it in the board’s crushing power or its price tag ($1995, less RAM and processor)?