Difficult to program

simpler design of compiler

Many addressing modes causing complex instructions formats

Low clock cycle per second

Emphasis is on software

Faster Execution

in RISC each instruction is to be executed by

in CISC instructions are to be read from memory and

Emphasis is on hardware

Few addressing modes, fix instructions formats

Higher clock cycle per second

Complex design of a compiler

Processors now operate at a clock frequency of 2 MHz.

Earlier generation microprocessors’ fetch–and–execute
cycle was guided by a clock frequency of order of 1 MHz

A microprocessor is a single VLSI chip having a CPU

A .... is a single–chip VLSI unit

is also called as microcomputer

Single task oriented

RAM,ROM, I/O ports, Timers can be added externally and can vary in numbers