Digital Electronics - Microprocessor Fundamentals - Discussion

For the 8085 microprocessor there are 3 buses..
They are
1.Adress Bus
2.Data Bus
3.Control Bus

Before knowing about the buses that are available in 8085 it is better to know the literal meaning of bus.

The bus is nothing but a group of wires used to process(or)communicate between different parts of the processor as well as computer.

In 8085 we have Three Buses that are 1) Address Bus 2) Data Bus 3) Control Bus.

The point we need to know here is out of these three buses which is Unidirectional and which is comes under Bidirectional buses.

Out of these three buses the address bus is bidirectional and remaining two buses are Unidirectional.

I hope this information is useful to you.

Address bus is unidirectional. Data bus is bidirectional.

Address bus is unidirectional as adress is generated by microprocessor and it is provided to i/o devices as well as memory when a read and write operation is done.

Data bus is bidirectional as data signal can flow from microprocessor to i/o devices, memory and vice versa.

The address bus is unidirectional because it is the CPU that tells the external hardware what address to use, not the other way around.

To communicate with memory the microprocessor sends an.

Address on the address bus, eg 0000000000000011 (3 in decimal) , to the memory. The memory the selects box number 3 for reading or writing data.

Address bus is unidirectional, ie numbers only sent from microprocessor to memory, not other way.

Address bus is unidirectional, and its obvious because, only MPU needs to know the address of data or peripheral device, so it is unidirectional.

Data bus is bidirectional, because data must be send or receive by the MPU and peripheral device, so its bidirectional.

Address bus is unidirectional but due to limited pin-counts (hardware) mostly higher order address bus is multiplexed with data bus and that is bidirectional.

Why the name microprocessor? not nano processor or mini processor?

@S.P.

It is called microprocessor because processor is designed with micro-technology. Because of quantum tunneling to make size more small micro technology is not possible. Nano processors are in invention stage. You can invent it.

@S.P.

Its named microprocessor. Because it require Micro seconds for processing. i.e. Crystal frequency which we used here is in terms of MHZ.