Computer organization and architecture solutions

COMPUTER ORGANIZATION AND ARCHITECTURE SOLUTIONS PC

Every statement written in a register transfer notation implies a hardware construction for implementing the transfer. P is a control signal generated in the control circuit. Alternatively, we can say if (P=1) then ( R2 R1 ). P: R2 R1 When condition P occurs, the contents of register R1 are copied into register R2. Abdul Hafez, ATRI 12-Oct-16ДЎ1 Register Transfer R2 R1 denotes a transfer of the content (copy) of register R1 (source register) into register R2 (destination register). Abdul Hafez, ATRI 12-Oct-16ДЎ0 Basic Symbols for Register Transfers Symbol Description Examples Letters (and numerals) Parentheses ( ) Arrow Comma, Denotes a register Denotes a part of a Register Denotes transfer of information Separates two microopeartions MAR, R2 R2(0-7), R2(L) R2 R1 R2 R1, R1 R2 10 Computer Organizatrion - Dr.

COMPUTER ORGANIZATION AND ARCHITECTURE SOLUTIONS PC

R1 (a) Register R (b) Showing individual bits R2 PC (H) PC (L) (c) Numbering of bits (d) Divided into two parts 9 Computer Organizatrion - Dr. The individual flip-flops (bits) are distinguished by writing the location number of the bit as in (b) or ( c) and (d) in the figure. In diagrams, the registers are represented by rectangular box with the name of the register inside as shown in the Figure. Examples: R1 processor register, PC Program Counter, AC Accumulator.

Abdul Hafez, ATRI 12-Oct-16Д© Register Representation Computer registers are designated by capital letters (sometimes followed by numerals) to define the function of the register. The control that initiates the sequence of Microoperations. The sequence of Microoperations performed on these registers. Abdul Hafez, ATRI 12-Oct-16ДЁ Hardware organization Internal hardware organization of a computer is best defined by: 1. A microprocessor performs the microoperations in order to realize the instruction. An instruction is fetched from memory, decoded and executed by performing a sequence of microoperations. Microoperations are the basis for Microprocessors. Digital modulus ( Ex: microprocessor) are best defined by the registers they contain and the operations that performed on the data stored in them. Examples of microoperations are: transfer, shift, clear and load. Abdul Hafez, ATRI 12-Oct-16Д§ Microoperations The operations that are performed on the data stored in registers are called microoperations. Different types of Shift Registers are available: 6 Computer Organizatrion - Dr. Shift Register is a group of Flip Flops connected together to save and shift n-bit data. To save n-bit, we need n Flip Flops connected together. HKUД¦ Registers Single Flip-Flop can save information of 1 bit. The additional circuits play the role of MUX whose outputs drive data to the register either from the data bus or from the output of the register it self. To leave the content of the register unchanged, the input must held constant or the clock should be prohibited. If all the bits of register are loaded simultaneously with a common clock pulse, the loading is called parallel load. HKUД¤ Register with parallel load Transferring new information into the register is called loading the register. Clear input (low active) reset the all outputs to 0s. Clock inputs triggers all flip flops at the positive (rising) edge of each pulse. HKUДЈ Registers A register is a group of flip flops, each of which is capable of storing one bit of information. Constructing bus system using three-state buffers 10. Constructing bus system using multiplexers 9. Illegal Simultaneous Register Transfers 6. 1 Computer Architecture and Organization: L03: Register transfer and System Bus By: A.

Computer organization and architecture solutions