When assembly still matters in embedded work, how an assembler produces object code, and what the linker does with it.

Motorola’s 68000 ran the first Macs and a generation of controllers; PowerPC ran the later Macs and still runs cars and aircraft. What the two architectures were and where they survive.

The TMS32010 shipped in 1983. It had 144 words of on-chip data RAM, a 16 by 16 multiplier that produced a result in one instruction cycle, and a

By the mid-nineties the PC industry had a fast, cheap, well-supported bus, and the industrial world had mechanics that could survive a factory floor. CompactPCI, published in 1995,

A real-time system is not a fast system. It is a system whose worst case is known. The distinction decides the architecture, the operating system, and often the

Selecting a part for a product with a ten-year service life is a sourcing decision wearing an engineering costume. Peripherals and clock speed decide whether the design works.

PC/104 solved a mechanical problem before it solved an electrical one. An industrial controller that has to survive vibration cannot rely on a card edge sitting in a

VMEbus was specified in 1981 around the Motorola 68000 and the Eurocard mechanics that European instrument makers already had on the shelf. Forty years later there are still