Circuit Project Electronic

Programmable Switch Mode Controllers (PSMC) are not just for switching power supplies. This technical brief describes how to use the PIC16C781 PSMC in combination with the Integrated Operational Amplifier, Digital-to-Analog Converter (DAC), and gated timer to construct a thermally operated air flow sensor with minimum external components.
Read more original source:
http://www.microchip.com/stellent/

The PICmicro ® microcontroller makes an ideal choice for an embedded DC Servomotor application. The PICmicro family has many devices and options for the embedded designer to choose from. Furthermore, pin compatible devices are offered in the PIC16CXXX and PIC18CXXX device families, which makes it possible to use either device in the same hardware design. [...]

Our next program will allow you to control the direction of the servo manually via a SPDT switch (with a center-off position) connected to ports B1 and B2. Without a center-off position, you will have to use two switches. A schematic is shown in figure 3 (below).
Read more original source:
http://www.imagesco.com/articles/picservo/03.html