PICs
I was just browsing Jack Ganssle's web site and when I saw this bit (http://www.ganssle.com/articles/asmall.htm) excerpted below:
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I'm fascinated with Microchip's PIC16/17 processors, which seem to be squeezing into a lot of low end applications. These are cool parts. The smaller members of the family offer a minimum amount of compute capability that is ideal for simple, cost-sensitive systems. Higher-end versions are well suited for more complicated control applications
Designer's seem to view these CPUs as something other than computers. "Oh, yeah, we tossed in a couple of PIC16s to handle the microswitches," the engineer relates, as if the part were nothing more than a PAL. This is a bit different from the bloodied, battered look you'll get from the haggard designer trying to ship a 68030-based controller. The microcontroller is easy to use simply because it is stuffed into easy applications.
L.A. Gear sells sneakers that blink an LED when you walk. A PIC16C5x powers these for months or years without replacing the battery. Scientists tag animals in the wild with expendable subcutaneous tracking devices powered by these parts. Household appliances depend on PIC variants.
A friend developing instruments based on a 32 bit CPU discovered that his PLDs don't always properly recover from brown-out conditions. He stuffed a $2 Microchip controller on the board to properly sequence the PLD's reset signals, insuring recovery from low-voltage spikes. The part costs virtually nothing, required no more than a handful of lines of code, and occupies the board space of a small DIP. Though it may seem weird to use a full computer for this trivial function, it's cheaper than a PAL.
Not that there's anything wrong with PALs. Nothing is faster or better at dealing with complex combinatorial logic. Modern super-fast versions are cheap (we pay $12 in singles for a 7 nanosecond 22V10), easy to use, and their reprogramability is a great savior of designs that aren't quite right. PALs, though, are terrible at handling anything other than simple sequential logic. The limited number of registers and clocking options means you can't use them for complicated decision making. PLDs are better, but when speed is not critical a computer chip might be the simplest way to go.
As the industry matures lots of parts we depend on become obsolete. One acquaintance found the UART his company depended on no longer available. He built a replacement in a PIC16C74, which was pin-compatible with the original UART, saving the company expensive redesigns.
In the good old days of microcomputing hardware engineers also wrote and debugged all of the system's code. Most systems were small enough that a single, knowledgeable designer could take the project from conception to final product. In the realm of small, tractable problems like those just described, this is still the case. Nothing measures up to the pride of being solely responsible for a successful product; I can imagine how the designer's eyes must light up when he sees legions of kids skipping down the sidewalk flashing their L.A. Gears at the crowds.
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I remembered this thread and thought it would add some credibility to the "Professional" camp. Microchip hasn't sold 3 BILLION PICs to hobbyists alone!
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