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Difference between direct addressing mode and indirect addressing modein8085 microprocessor?
Wiki User
∙ 14y ago
When a microprocessor wants to store a byte of information in memory, or retrieve a byte of information from memory, it needs to refer to the address of the byte in the instruction. When direct addressing is used then the microprocessor instruction refers explicitly to the address that is to be used. When indirect addressing is used then the microprocessor instruction refers to a third object that refers to the address that is to be used. So, for example: Direct addressing: (*) Store the data at address 0x3C6E (*) Deliver the letter to house 12 on the street. Indirect addressing: (*) Store the data at whatever address is in register AX. (*) Deliver the letter to whichever house the occupant of house 7 tells you. So, in indirect addressing, the microprocessor instruction refers to some other "third-party" location (a register or another memory location) to find-out what the ultimate address to be used should be. The instruction does not contain all of the information needed to store the byte (or deliver the letter) but it does say where the missing information can be found. In direct addressing, the instruction contains all of the information needed to store the byte (or deliver the letter). This is basically true for all microprocessors but different microprocessors allow different forms of indirect addressing. For example, some use memory indirect addressing (the third party is another memory location), and some use register indirect addressing (the third party is a register).
Wiki User
∙ 15y ago
Wiki User
∙ 14y agoDirect addressing mode is where the address of the operand is contained in the instruction. Indirect addressing mode is where the address of the operand is contained in a register pair, usually HL.
Wiki User
∙ 14y agoIndirect addressing mode in an 8085 is when the address of the operand is contained within a register, rather than directly within the instruction itself. Instructions that do this are LDAX, STAX, and any of the move, arithmetic, logical, or compare instructions that use M as the source or destination.
Wiki User
∙ 13y agoImmediate addressing mode is where the operand is contained in the instruction. For example...
ADI 3
...adds 3 to the accumulator, and the constant 3 is located immediately following the opcode for ADI.
Wiki User
∙ 14y agoDirect addressing is used to access the SFRs whereas indirect addressing is used to access the RAM space shared by these SFRs with the scratchpad RAM.
Wiki User
∙ 13y agoImmediate addressing mode is when one of the operands is "immediately" located after the opcode. It is more correct to say that the operand is part of the instruction.
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What is difference between direct addressing and indirect addressing in c plus plus?
Indirect addressing uses a pointer. Indirectly accessing the memory being pointed at is known as dereferencing. Direct addressing uses a variable's name or a reference to obtain the value.
What are addressing mode in microprocessor?
Addressing modes of 8051 are 1.Immediate Addressing Mode 2.Register Addressing Mode 3.Register Indirect Addressing Mode 4.Direct Addressing Mode 5.Implied Addressing Mode and 6.Relative Addressing Mode
What are the different types of addressing modes?
literal and absolute direct are the registers
What are the costs and benefits of indirect addressing?
Feces and smells.
What is defference between direct and indirect address?
Direct addressing involves specifying the exact memory address where data is stored or fetched. Indirect addressing involves using a memory address that points to where the data is stored or fetched. In direct addressing, the actual data is accessed, while in indirect addressing, a reference to the data's location is accessed.
How many addressing mode of 8086 assembly language program?
there are five addressing modes in 8086 they are : 1->direct addressing 2->Indirect addressing 3->index addressing 4->immediate addressing 5->register addressing
How many pins are present in 8085 and 8086 microprocessor?
There are 256 ports available in the 8085 microprocessor. The IN and OUT instructions have an 8-bit port number, and that is where the 256 comes from.In order to use ports, the hardware addressing system must decode IO/M-. Some implementations don't do this, so they map IO addresses to memory addresses. In that case, you could say there are 65536 possible IO addresses, but that is not the same as ports, because ports are specific to the IN and OUT instructions.The other "problem" with IN and OUT is that you cannot specify the address in a register, while you can do so with indirect memory addressing.
How does 8085 access data from memory location?
Data can be accessed from memory by using the addressing modes, 8085 has 5 addressing modes namely,1. Immediate addressing mode 2. register addressing mode 3. direct addressing mode 4. indirect addressing mode 5. implied addressing mode
What is diffeence between a microprocessor and microprogramed?
Do you mean what is the difference between a microprocessor and microcode? Microcode is an instruction sequencer found in CISC architectures. It's job is to take the machine code and break it down into a sequence (usually steps of 4) to execute things such as indirect register references and other multi-step instructions.
What is addressing mode of instruction?
Addersing mode of a microprocesso tells the programmer that in which mode the instruction works . There are 5 addressing mode in 8080 , viz. Direct , register, indirect , immidiate ,implict addressing modes.
What are the adressing modes of 8085 microprocessor?
Different Addressing modes are: 1. Direct Addressing Mode 2. Indirect Addressing Mode 3. Immediate Addressing Mode 4. Register Addressing Mode 5. Implicit Addressing Mode Immediate addressing Data is present in the instruction. Load the immediate data to the destination provided. Example: MVI R,data Register addressing Data is provided through the registers. Example: MOV Rd, Rs Direct addressing Used to accept data from outside devices to store in the accumulator or send the data stored in the accumulator to the outside device. Accept the data from the port 00H and store them into the accumulator or Send the data from the accumulator to the port 01H. Example: IN 00H or OUT 01H Indirect Addressing This means that the Effective Address is calculated by the processor. And the contents of the address (and the one following) is used to form a second address. The second address is where the data is stored. Note that this requires several memory accesses; two accesses to retrieve the 16-bit address and a further access (or accesses) to retrieve the data which is to be loaded into the register.
What is the purpose of DI register in microprocessor in 8086?
DI is the Index register in Data segment(16-bit, 64 KB) .Destination Index (DI) is a 16-bit register. DI is used for indexed, based indexed and register indirect addressing, as well as a destination data address in string manipulation instructions.
