Dr C.Naveeth Babu

  A set of flip-flops forms a register. A register is a unique high-speed storage area in the CPU. They include combinational circuits that implement data processing. The information is always defined in a register before processing. The registers speed up the implementation of programs. Registers implement two important functions in the CPU operation are as follows − It can support a temporary storage location for data. This supports the directly implementing programs to have fast access to the data if required. It can save the status of the CPU and data about the directly implementing program. Example  − Address of the next program instruction, signals get from the external devices and error messages, and including different data is saved in the registers. The CPU bus system is managed by the control unit. The control unit explicit the data flow through the ALU by choosing the function of the ALU and components of the system. Consider R1 ← R2 + R3, the following are the functions imp

  Implied / Implicit Addressing Mode Stack Addressing Mode Immediate Addressing Mode Direct Addressing Mode Indirect Addressing Mode Register Direct Addressing Mode Register Indirect Addressing Mode Relative Addressing Mode Indexed Addressing Mode Base Register Addressing Mode Auto-Increment Addressing Mode Auto-Decrement Addressing Mode 1. Implied Addressing Mode-   In this addressing mode, The definition of the instruction itself specify the operands implicitly. It is also called as  implicit addressing mode .   Examples-   The instruction “Complement Accumulator” is an implied mode instruction. In a stack organized computer, Zero Address Instructions are implied mode instructions. (since operands are always implied to be present on the top of the stack)   2. Stack Addressing Mode-   In this addressing mode, The operand is contained at the top of the stack.   Example-   ADD This instruction simply pops out two symbols contained at the top of the stack. The addition of those two opera