Q37. Explain the role and purpose of data and address bus.
Data Bus: Data bus carries data, in binary form, between the processor and external units, such as memory. Its typical size is 8 or 16 bits. The data bus consists of 8 wires, i.e., 256 combinations of binary digits. The data bus is bidirectional it can carry information in both directions CPU to memory and vice versa.
Address Bus: The address bus carries memory addresses. It has one wire for each bit, therefore 16 bits 16 wires. The memory address carried by the bus alerts memory to on the designated box. To communicate with memory, a microprocessor sends a address to address bus, to the memory. The memory then selects box number 3 for reading or writing
Address bus is unidirectional, i.e., addresses are send from microprocessor to memory, not the other way.