Specifications

Computer Architecture and Maintenance (G-Scheme-2014)
or receive data. The data bus also works as address bus when multiplexed with lower
order address bus. Data bus is 8 Bits long. The word length of a processor depends on
data bus, thats why Intel 8085 is called 8 bit Microprocessor because it have an 8 bit
data bus.
To increase the amount of data being sent (called bandwidth) by increasing either
the cycling time or the number of bits being sent at a time, or both. Over the years,
processor data buses have gone from 8 bits wide to 64 bits wide. The more wires you
have, the more individual bits you can send in the same interval. All modern
processors from the original Pentium and Athlon through the latest Core i7, AMD FX
83xx series, and even the Itanium series have a 64-bit (8-byte)-wide data bus. Therefore,
they can transfer 64 bits of data at a time to and from the motherboard chipset or
system memory.
Wider the bus more is the speed ie 64-bit-wide buses. Also in newer processors
is the use of multiple separate buses for different tasks. Traditional processor design
had all the data going through a single bus, whereas newer processors have separate
physical buses for data to and from the chipset, memory, and graphics card slot(s).
Control Bus:
Microprocessor uses control bus to process data, that is what to do with the
selected memory location. Some control signals are Read, Write and Opcode fetch etc.
Various operations are performed by microprocessor with the help of control bus. This
is a dedicated bus, because all timing signals are generated according to control signal.
Prepared By – Prof. Manoj.kavedia (9860174297 – 9324258878 ) (www.kavediasir.yolasite.com)
3