Download - REGISTER TRANSFER & MICROOPERATIONS
REGISTER TRANSFER&
MICROOPERATIONS
By Sohaib
Digital System Overview
Each module is built from digital components Registers Decoders Arithmetic elements Control logic
Collection of modules is a digital system.
Modules connected by common data and control paths.
Microoperations
Elementary operation performed on data within one or more registers
Operation result could update same register or another register
Examples: shift, count, clear, and load Bidirectional shift can shift left or shift
right Counter with parallel load can
perform count and load.
Internal Hardware Organization
Can be defined by specifying Set of registers and their functions Sequence of microoperations performed on
register data Control that initiates the sequence of
microoperations Can use words to express sequence of
microoperations, but it’s better to use a notation and symbols Register Transfer Language
Registers
Capital letter sometimes followed by a number
MAR– memory address register PC– program counter IR– instruction register R1,R2 – processor register 1, process
register 2 Each flip-flop in a n-bit register is
numbered from n-1 to 0 from left to right.
Register Block Diagram
Register Transfer
Control Function
P: R2 R1 Block Diagram
2nd Register Transfer Example
Bus Transfers
Bus System For 4 Registers
Bus Details
Memory Transfer
Microoperations Summary
Add & Subtract
Arithmetic Microoperations
Binary Adder
4-bit Binary Adder
Binary Adder-Subtractor
Binary Adder-Subtractor
Binary Incrementer
Binary Incrementer
Arithmetic Circuit
4-Bit Arithmetic Circuit
Arithmetic Circuit Function Table
4-Bit Arithmetic Circuit
Logic Micro operations
Special Symbols
16 Logic Micro operations- Part 1
16 Logic Micro Operations – Part 2
Hardware Implementation
One Stage of Logic Circuit
Shift Micro Operations
Logical Shift Example
Circular Shift Example
Arithmetic Shift Example
Shift Micro Operations
Shift Hardware Implementation
4-Bit Combinational Circuit Shifter