0
Because that is the way Intel designed the INX instruction of the 8085. The 8080 is also the same. INX increments (and DCX decrements) the 16 bit register pairs or BC, DE or HL, depending on what register pair you specify in the INX (or DCX) instruction. To check is the value is 0 after an INX (or DCX) instruction, you need to OR the values of the register pair into the A register. For example.....
INX H ;increment HL register pair
MOV A,H ; move H register into the accumulator
ORA L ; Logical OR it with the L register
JZ ADDR ; If 0 then jump to ADDR
What else can I help you with?
How you can calculate zero flag in 8085 microprocessor?
In the 8085 microprocessor, the Zero Flag (Z) is set or cleared based on the result of an arithmetic or logical operation. Specifically, the Zero Flag is set to 1 if the result of the operation is zero; otherwise, it is cleared to 0. To calculate the Zero Flag, the microprocessor checks the result of the last executed instruction and updates the flag accordingly. This flag can be used in conditional branching to determine if further operations should be performed based on whether the result was zero.
What is dad and what are the flags affected by dad in 8085?
In the 8085 microprocessor, DAD (Double Add) is an instruction that adds the contents of a specified 16-bit register pair (HL, BC, or DE) to the contents of the accumulator (A) and stores the result back in the 16-bit register pair. The flags affected by the DAD instruction are the Carry flag (CY) and the Parity flag (P). The Zero flag (Z) and Sign flag (S) remain unaffected. Additionally, the Auxiliary Carry flag (AC) is also not affected by this operation.
What is the flag in 8085 can't access directly?
In the 8085 microprocessor, the flag that cannot be accessed directly by the programmer is the "Auxiliary Carry Flag" (AC). This flag is primarily used for binary-coded decimal (BCD) arithmetic operations and is not directly accessible through the instruction set. While other flags like the Sign, Zero, Parity, Carry, and Auxiliary Carry can influence program control, the Auxiliary Carry is typically manipulated indirectly through specific arithmetic instructions.
What is the role of Flag in 8085 MP?
In the 8085 microprocessor, the flag register is a special register that contains five status flags: sign, zero, auxiliary carry, parity, and carry. These flags are used to indicate the status of the arithmetic and logical operations performed by the CPU. They help in decision-making during program execution, particularly in conditional branching. The flags are updated automatically after each instruction execution, reflecting the outcome of the operation.
What is the importance of flags in microprocessor?
sign flag parity flag zero flag
What is the effect of operating different instruction on psw in 8085?
In the 8085 microprocessor, the Program Status Word (PSW) contains important flags that reflect the state of the processor. Different instructions can affect these flags, such as the Zero Flag, Sign Flag, Carry Flag, and Parity Flag. For example, arithmetic operations like addition or subtraction can set or reset these flags based on the result of the operation. Consequently, the PSW is essential for conditional branching and decision-making within programs, as it provides the necessary status information determined by the executed instructions.
What is CMP in 8085 microprocessor?
In the 8085 microprocessor, CMP (Compare) is an instruction used to compare the contents of the accumulator (register A) with another specified register or memory location. It effectively subtracts the value of the specified operand from the accumulator but does not store the result; instead, it sets the status flags (zero, carry, and sign) based on the outcome of the comparison. This allows for conditional branching in programs, as the results can be used to determine the flow of execution. The CMP instruction helps in decision-making processes within the microprocessor's operation.
What are the various flags used in 8085?
there are 5 flags of intel 8085 are: Carry flag(CY), parity flag(P), Auxiliary Carry flag(AC), Zero Flag(Z), Sign flag(S).
What are the status flags in 8085?
In the 8085 microprocessor, the status flags are specific bits in the flag register that indicate the outcome of arithmetic and logical operations. There are five main flags: the Sign Flag (S), Zero Flag (Z), Auxiliary Carry Flag (AC), Parity Flag (P), and Carry Flag (CY). The Sign Flag indicates the sign of the result, the Zero Flag indicates if the result is zero, the Auxiliary Carry Flag is used for BCD operations, the Parity Flag indicates if the number of set bits is even or odd, and the Carry Flag indicates an overflow in arithmetic operations. These flags are essential for decision-making in program execution and control flow.
What are the instruction for make content of accummulator zero in 8085?
Sub a ani 00h xra a
What are the flags affected by ALU in 8085 Explain briefly?
In the 8085 microprocessor, the Arithmetic Logic Unit (ALU) affects five flags in the status register: Sign Flag (S), Zero Flag (Z), Auxiliary Carry Flag (AC), Parity Flag (P), and Carry Flag (CY). The Sign Flag indicates the sign of the result; the Zero Flag is set if the result is zero; the Auxiliary Carry Flag is used for BCD operations; the Parity Flag indicates whether the number of 1s in the result is even or odd; and the Carry Flag indicates an overflow in arithmetic operations. These flags help in decision-making for subsequent operations and control flow in programs.
Explain different types of flags in 8085 microprocessor?
Flags are microprocessor dependent. ie flags are different for different microprocessors. Flag represents the status ( & Type) of the operation performed. Ex: In terms of 8085 we have 5 flags : Zero, Carry, Ac Carry, Parity, Sign Flag register is of 8 bits in this case. These flags can also be used for logic implementation.
