The simplest way to examine the advantages and disadvantages of RISC architecture is by contrasting it with it’s predecessor: CISC (Complex Instruction Set. RISC and CISC Architectures – Difference, Advantages and . Disadvantages of CISC Architecture: Disadvantages of RISC Architecture. RISC and CISC are two architectures used for designing of Advantages of CISC Architecture Disadvantages of RISC Architecture.

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RISC processors require very fast memory systems to feed various instructions.

RISC and CISC Architectures – Difference, Advantages and Disadvantages

Only load and store instructions have memory access. There is one instruction per machine cycle in RISC processor. Due to this one cycle instruction, execution of instructions carried at a faster rate compared with microinstructions on CISC processor.

Many CISC architectures, read the inputs and write their outputs in the memory system instead of a register file. In CISC based processor, control signals for the execution of dksadvantages instruction are generated by a microprogram execution. The major characteristics of CISC architecture are. Addressing modes are the manner in the data is accessed. The speed of the execution is increased by using smaller number dsadvantages instructions as compared with single long instruction in case of CISC architecture.

Because, the large programs need more storage, thus increasing disadvqntages memory cost and large memory becomes more expensive. It uses a lesser number of addressing modes. It consists of 8 to 24 general purpose registers with a unified cache for instructions and data recent designs use split caches.


The conditional codes are set by the CISC instructions as a side effect of each instruction which takes time for this setting — and, as the subsequent instruction changes the condition code bits — so, the compiler has to examine the condition code bits before this happens. Team Electronic Pull is manage by two friends from Pakistan. Thus, the “MULT” command described above could be divided into three separate commands: A compiler translates high level language to machine language.

Thus, they share the same path for both instructions and data. There are two prevalent instruction set architectures.

Ahd are in the form — Opcode operational code and Operand. CISC designs involve very complex disadvantagse, including a large number of instructions and addressing modes, whereas RISC designs involve simplified instruction set and adapt it to the real requirements of user programs. This architecture makes the efficient use of main memory since the complexity or more advantagew of instruction allows to use less number of instructions to achieve a given task.

In CISC processor, most instructions are stored in memory and they are executed by microprogram. Therefore, CISC has the variable length encoding of instructions and the number of clock cycles required to execute the instructions may be varied. The per-chip cost is reduced by this architecture that uses smaller chips consisting of more components on a single silicon wafer.


Typically, a large memory cache is provided on the chip in most RISC based systems. It supports complex addressing modes In this complex addressing modes are synthesized in software.

What is RISC and CISC Architecture with Advantages and Disadvantages

For feeding the instructions, they require very fast memory systems. To find out more, including how to control cookies, see here: Computers based on the CISC architecture are designed to decrease the memory cost.

CISC design is a 32 bit processor and four bit floating point registers. Instructions are not pipelined or less pipelined. The processor is controlled using microcoded control memory modern CISC processor also uses hardwired control.

The Advantages and Disadvantages of RISC and CISC | Vinod kadam……..

Spends more transistors on memory registers. Email required Address never made public. In this complex addressing modes are synthesized in software. Single-clock, reduced instruction only.

It is easy to add new commands into the chip without changing the structure of the instruction set as the architecture uses general-purpose hardware to carry out commands.