PIC MicrocontrollerBrief HistoryThe first microprocessor was developed by a small company called Intel (Integrated Electronics) in the early 1970s. But it didn't have a consumer market, so they decided to market the chipset as a "general purpose" microprocessor system where digital logic chips would be used. This idea was a success and the Intel team developed a 4-bit microprocessor called the 4004. In 1974, the second generation microprocessor (the 8080) was manufactured as a single chip driven by a +5 V power supply. Meanwhile Motorola released its first 8-bit microprocessor, the 6800. with the same processing power as the Intel 8080. But their internal structures are slightly different. In the 8008 a register based architecture is used with separate I/O memory accessed via typical MOV instructions where the Motorola 6800 used "O mapped I/O memory" meaning both memory and Byte-level input/output share the same memory map. In the case of Intel's range of new microprocessors, the 8080 developed further into the 8085 and then into the third generation 16-bit 8086 microprocessor which, in its pseudo 8088 16-bit format. The 8088 was an 8086 but with only an 8-bit data bus. 8088 made it easier to interface with common 8-bit peripherals available at the time. Today, the 800386 (a 32-bit processor) and the 80486 are available. These processors are designed for large memory maps. Motorola developed the 6800 replaced by the 6809 (8 bit), then the 68000 (16 bit), the 68010, 68020 and 68030 used in many workstations. More recent development in microprocessor architectures such as the Harvard architecture and the use of reduced instruction set computers (RISC) have led to the development of microcontrollers such as the Microchip PIC....... middle of paper.. ....USB communication and connectivity.FIG 4: PIC 18F4550 Interface Circuit Technical Details of Interface Circuit Circuit Parts Specifications: • MCU: PIC 18F4550. • Power LED: LED to indicate power status. • Snubber Capacitor: A 100 nf non-polar capacitor is used to (dampen) dampen/remove any noise in the input power supply to the MCU. • Oscillator: An 8 MHz quartz crystal serves the oscillator along with two 25 pf decoupling capacitors on the input and output OSC pins. • Master Clear Resistor: A weak 1K ohm pull up resistor on the !MCLR pin inhibits reset during MCU Operation. • Reset Switch: The switch can be used to manually reset the MCU to start program execution from the beginning. • Analog channels: 4 open analog channels are available for interfacing with circuits. Available channels: AN0, AN1, AN2, AN3