QUESTIONS AND PROBLEMS 7.1 It is desired to implement the following instructions using block code: ADD, SUB, XOR, MOVE, HALT. Draw a block diagram. 7.2 The instruction length and the size of an address field are 9 bits and 3 bits respectively. Is it possible to have 6 two-address instructions 15 one-address instructions 8 zero-address […]
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DESIGN OF COMPUTER INSTRUCTION SET AND THE CPU
Design of a Microprogrammed CPU
7.4 Design of a Microprogrammed CPU Next, the design of a microprogrammed processor is illustrated. The programming model of this processor is shown in Figure 7.52. The CPU contains two registers: 1. An 8-bit register A 2. A 2-bit flag register F The flag register holds only zero (Z) and carry (C) flags. All programs […]
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Microprogrammed Control Unit Design
Microprogrammed Control Unit Design As mentioned earlier, a microprogramm d contwl unit contains programs written using microinstructions. These programs are stored in a control memory normally in a ROM inside the CPU. To execute instructions, the microprocessor reads (fetches) each instruction into the instruction register from external memory. The control unit translates the instruction for […]
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Alu design , design of the control unit , basic concepts and hardwired control design
7.3.4 ALU Design Functionally, an ALU can be divided up into two segments: the arithmetic unit and the logic unit. The arithmetic unit performs typical arithmetic operations such as addition, subtraction, and increment or decrement by 1. Usually, the operands involved may be signed or unsigned integers. In some cases, however, an arithmetic unit must […]
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Design of computer instruction set and the cpu : desi n of the cpu ,register design and adders
7.1 Desi n of the CPU The CPU contains three elements: registers, the ALU (Arithmetic Logic Unit), and the control unit. These topics are discussed next. Verilog and VHDL descriptions along with simulation results of a typical CPU are provided in Appendices I and J respectively. 7.3.1 Register Design The concept of general-purpose and flag […]
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Addition, Subtraction, Multiplication and Division of unsigned and signed numbers
7.3.3 Addition, Subtraction, Multiplication and Division of unsigned and signed numbers The procedure for addition and subtraction of two’s complement signed binary numbers is straightforward. The procedure for adding unsigned numbers is discussed in Chapter 2. Also, addition of two 2’s complement signed numbers was included in Chapter 2. Note that binary numbers represented in […]
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DESIGN OF COMPUTER INSTRUCTION SET ANDTHECPU: Design of the Computer Instructions and Reduced Instruction Set Computer (RISC)
DESIGN OF COMPUTER INSTRUCTION SET ANDTHECPU This chapter describes the design of the instruction set and the central processor unit (CPU). Topics include op-code encoding, design of typical microprocessor registers, the arithmetic logic unit (ALU), and the control unit. 7.1 Design of the Computer Instructions A program consists of a sequence of instructions. An instruction […]
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