Difference Between Microprocessor and Microcontroller: Microprocessor is an IC which has only the CPU inside them. These microprocessors don’t have RAM, ROM, and other peripheral on the chip. A system designer has to add them externally to make them functional. Microcontroller has a CPU, in addition with a fixed amount of RAM, ROM and other peripherals all embedded on a single chip. At times it is also termed as a mini computer or a computer on a single chip. Some manufacturers are ATMEL, Microchip, TI, Freescale, Philips, Motorola etc. ...