Explain the following instructions with respect to its description, memory capacity, word length, addressing mode, no. of machine cycles and flags affected :- (i) STAX B (ii) LHLD 2500H (iii) LXI SP, 2100H (iv) ADC M (v) MOV M,B

The 8085 microprocessor is an 8-bit microprocessor, meaning it has a word length of 8 bits. This means it can manipulate and store data that is 8 bits wide. It has a memory capacity of 64 KB, which is 64 kilobytes. This means it can access and use up to 64 kilobytes of memory.

The instructions you have provided are all instructions for the 8085 microprocessor. Here is a brief description of each one:

(i) STAX B: This instruction is used to store the contents of the accumulator (A) into the memory location pointed to by the B register. The B register is one of the 6 general-purpose registers in the 8085 microprocessor. This instruction uses the register indirect addressing mode. This instruction takes 2 machine cycles to execute and does not affect any flags.

(ii) LHLD 2500H: This instruction is used to load the contents of the memory location specified in the instruction (2500H in this case) into the H and L registers. The H and L registers are used to store 16-bit memory addresses in the 8085 microprocessor. This instruction uses the register direct addressing mode and takes 5 machine cycles to execute. It does not affect any flags.

(iii) LXI SP, 2100H: This instruction is used to load the 16-bit value specified in the instruction (2100H in this case) into the stack pointer (SP) register. The SP register is used to store the address of the top of the stack in the 8085 microprocessor. This instruction uses the immediate addressing mode, which means the value is specified directly in the instruction. It takes 3 machine cycles to execute and does not affect any flags.

(iv) ADC M: This instruction is used to add the contents of the memory location pointed to by the H and L registers to the contents of the accumulator (A) and store the result in the accumulator. The H and L registers are used to store the memory address of the location to be accessed. This instruction uses the indirect addressing mode, which means the memory location is specified indirectly through the H and L registers. It takes 2 machine cycle to execute and affects the carry flag (CY) and the auxiliary carry flag (AC).

(v) MOV M, B: This instruction is used to move the contents of the memory location pointed to by the H and L registers into the B register. The H and L registers are used to store the memory address of the location to be accessed. This instruction uses the register indirect addressing mode and takes 2 machine cycle to execute. It does not affect any flags.