What did computers without screens do?

On Mon, Dec 14, 2015 at 2:05 PM, Mike <tulsamike3434 at gmail.com> wrote: Even lighting... I've pulled (and reused!) 8-pin PIC microcontrollers out of discarded emergency lighting. "In the old days", a switching supply might have a 555 timer for an oscillator. These days, an 8-pin uC is cheap ($0.75 or far less) and allows the behavior to be changed without a soldering iron, or allows the hardware design to be completed and sent out for manufacture before the software is complete. If you want to change the frequency of a 555 oscillator, you have to design in a potentiometer or remove and install different value components. If you want to change the frequency of a uC oscillator, you reprogram it (or if you have enough pins, design in some removable jumpers). Short version is, even the cheap and simple 555 has been replaced in many products with a cheap-as-or-cheaper-than microcontroller, not because it's simpler, but because it allows for greater flexibility and reduces the overall product cost. -ethan