Comparison between RISC and CISC

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RISC CISC 
Emphasis on software  Emphasis on hardware 
Single-clock, reduced instruction only  Includes multi-clock complex instructions 
Register to register: Memory-to-memory:
"LOAD" and "STORE" are independent instructions "LOAD" and "STORE" incorporated in instructions 
large code sizes, Low cycles per second Small code sizes, High cycles per second 
Spends more transistors on memory registers Transistors used for storing complex instructions 
uses small and limited number of instructions. CISC chips have a large amount of different and complex instructions.
RISC processors uses simple addressing modes.  CISC machines generally make use of complex addressing modes. 
RISC machines uses hardwired control unit.  CISC machines uses micro-program control unit. 

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