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By Jack Ganssle


Published 4/16/2007

When Intel introduced the microprocessor in 1971 they quickly realized that the embedded apps spawned by this new invention were very different than conventional computer systems. Most had neither a keyboard nor a display, at least not one like the then-common VT-100 (DEC CRT terminals) or ASR-33 (beastly-loud mechanical teletypewriters). Programs lived in ROM. Developers had little visibility into what their code was doing.

They introduced the Intellec, a development platform originally for the 4004 and later the 8008. Intellecs were computers themselves with a UART for communication with a standard terminal. But many users, including yours truly, hotwired the unit's bus to that of the embedded system we were developing. Then one could download and (very tediously) debug applications.

By the mid-70s the company finally invented the true In-Circuit Emulator (ICE) in the guise of their MDS-800, then as now colloquially known as the "Blue Box". Packaged with the optional ICE boards these units cost some $20k, about $79k in today's dollars, and had dual 8" floppy disks, each of which stored 80KB if memory serves.

We swapped disks a lot.

ICEs came to dominate embedded development. By the 80s numerous companies specialized in these sorts of tools. The largest was Applied Microsystems, which at their peak sold some $40m worth of emulators every year.

Then the ICE world imploded.

Higher speeds, difficult-to-probe IC packages, and complex speed boosters (like caches, pipelines, MMUs, etc) all conspired to make emulators problematic at best. Motorola, TI and others introduced BDM and JTAG interfaces for debugging. IC vendors mostly stopped making bond-out versions of their chips, special high-pin count variants used only by ICE companies to create more visibility into the processors.

Applied Microsystems essentially failed in 2002. Many other emulator vendors weren't far behind. The industry is now a shell of its former self.

One of the giants of the business was Nohau, which originally specialized in emulators for the 8051 and derivatives. Over time they expanded into a number of other microcontrollers and to higher-end CPUs. They, too, joined the BDM revolution while continuing to offer traditional ICEs as well.

Nohau was privately-held so never published sales data, but my guess - and it's only a guess - pegged their yearly sales around the $10m mark during their heyday. That's a pretty small company, but in the small world of emulators was huge.

Nohau produced much more than a line of debugging products. They developed a sterling reputation as a company insanely responsive to customers, and one that sold a very high-quality line of products, a trait that often eluded some other ICE vendors. At the Embedded Systems Conferences their big booth was always packed with happy customers and interested prospects.

The technology challenges that hit other ICE vendors didn't leave Nohau unspared. Business changed, and then shrank. They disappeared from the ESC and their ads were no longer so prominent.

This year their parent company went bankrupt and Nohau itself stopped operations, due, according to my sources, more to legal issues unrelated to the emulator business than a lack of business. I was saddened when I heard that this great company and their highly-respected line of tools disappeared.

But in late-breaking news, the product line has been rescued by Ice Technology ( Owner Joe Pennese, long an emulator man and Nohau rep, bought the company's product line. He told me that sales are far above expectations.

Though I remain saddened at the scattering of Nohau's excellent staff, it's nice to know their products live on.

Do note that Nohau in the rest of the world is still alive and doing well, but according to their web sites, no longer sell the Nohau brand of emulator.

Do you have stories of using their products?