Question

How Accumulator is different than general purpose register in 8085 Microprocessor? 

Answer 1

Sr No.	Feature	Accumulator (Register A)	General Purpose Registers (B, C, D, E, H, L)
1.	Primary Role	Acts as the primary register for all arithmetic and logical operations.	Used for temporary storage of data and as memory pointers.
2.	ALU Connection	Directly connected to the ALU, it holds one of the operands for almost all operations.	Not directly connected to the ALU as a primary source for operands.
3.	Result Storage	The final result of an operation is automatically stored back here.	Cannot store the result of an operation directly; data must be moved from the Accumulator.
4.	Input/Output	Essential for I/O operations; data from input devices and to output devices must pass through it.	Generally, do not participate directly in data transfer with I/O devices.
5.	Register Pairing	It is not typically paired for 16-bit data operations in the same way.	Can be combined into 16-bit register pairs (BC, DE, HL) to address memory.
6.	Specific Instructions	Supports exclusive instructions such as DAA, CMA, and rotation instructions.	Limited to general data copy ( MOV ) and simple increment/decrement ( INR / DCR ).