Description of the problem:
Hall effect sensor was positioned so as to detect a shaft mounted “steal flag”.
The flag would pass the sensor once per revolution of the shaft. The sensor worked perfectly, however, the slower the shaft rotated, the more time it took for the flag to sweep by the sensor. At lower shaft speeds, the output pulse from the sensor was long enough to confuse the motion control computer.
The computer needed sensor feedback for positioning and it thought the shaft was rotating at 900 RPM instead of 40 RPM. You can imagine the potential for catastrophe.
The solution? Program a PIC 10F222 to perform as a one-shot. Now regardless of the length of the input pulse, the positioning computer receives a perfect, bounce-less, 5uS pulse. And the best part is that the10F series has an internal oscillator and no need for any ancillary components. All the chip needs is ~5V.