Data transfer instructions in 8085 microprocessor
Last Updated :
06 May, 2023
Data transfer instructions are the instructions that transfer data in the microprocessor. They are also called copy instructions. Here is the following is the table showing the list of logical instructions:
| OPCODE | OPERAND | EXPLANATION | No. of bytes | Machine cycles | No. of T-states | EXAMPLE |
|---|
| MOV | Rd, Rs | Rd = Rs | 1 | 1 opcode fetch | 4 | MOV A, B |
| MOV | Rd, M | Rd = Mc | 1 |
1 opcode fetch
1 memory read
| 7 | MOV A, 2050 |
| MOV | M, Rs | M = Rs | 1 |
1 opcode fetch
1 memory write
| 7 | MOV 2050, A |
| MVI | Rd, 8-bit data | Rd = 8-bit data | 2 |
1 opcode fetch
1 memory read
| 7 | MVI A, 50 |
| MVI | M, 8-bit data | M = 8-bit data | 2 |
1 opcode fetch
1 memory read
1 memory write
| 10 | MVI 2050, 50 |
| LDA | 16-bit address | A = contents at address | 3 |
1 opcode fetch
2 memory reads for 16-bit data
1 memory read for reading content at 16-bit address
| 13 | LDA 2050 |
| STA | 16-bit address | contents at address = A | 3 |
1 opcode fetch
2 memory reads
1 memory write
| 13 | STA 2050 |
| LHLD | 16-bit address | directly loads at H & L registers | 3 |
1 opcode fetch
2 memory reads for reading 16-bit data
2 memory reads for loading H and L registers
| 16 | LHLD 2050 |
| SHLD | 16-bit address | directly stores from H & L registers | 3 |
1 opcode fetch
2 memory reads for reading 16-bit data
2 memory write
| 16 | SHLD 2050 |
| LXI | r.p., 16-bit data | loads the specified register pair with data | 3 |
1 opcode fetch
2 memory reads
| 10 | LXI H, 3050 |
| LDAX | r.p. | indirectly loads at the accumulator A | 1 |
1 opcode fetch
1 memory read
| 7 | LDAX H |
| STAX | 16-bit address | indirectly stores from the accumulator A | 1 |
1 opcode fetch
1 memory write
| 7 | STAX 2050 |
| XCHG | none | exchanges H with D, and L with E | 1 | 1 opcode fetch | 4 | XCHG |
| XTHL | none | exchanges the content of the top of the stack with the content of HL pair | 1 |
1 opcode fetch
2 memory reads
2 memory writes
| 16 | XTHL |
| PUSH | r.p. | pushes r.p. to the stack | 1 |
1 opcode fetch
2 memory writes
| 12 | PUSH H |
| POP | r.p. | pops the stack to r.p. | 1 |
1 opcode fetch
2 memory reads
| 10 | POP H |
| IN | 8-bit port address | inputs contents of the specified port to A | 2 |
1 opcode fetch
1 memory read
1 I/O read
| 10 | IN 15 |
| OUT | 8-bit port address | outputs contents of A to the specified port | 2 |
1 opcode fetch
1 memory read
1 I/O write
| 10 | OUT 15 |
| | | | | | | |
In the table,
R stands for register
M stands for memory
r.p. stands for register pair
Advantages:
Efficient data transfer: The data transfer instructions in the 8085 microprocessor can move data quickly and efficiently between different registers, memory locations, and input/output ports.
Simplifies programming: The data transfer instructions in the 8085 microprocessor simplify programming by providing a set of dedicated instructions for transferring data.
Supports a wide range of operations: The data transfer instructions in the 8085 microprocessor support a wide range of operations, including loading data into registers, storing data in memory locations, and input/output operations.
Can be used for memory operations: The data transfer instructions can be used to transfer data between registers and memory locations, making it possible to store and retrieve data from memory.
Disadvantages:
Limited memory access: Although the use of registers can reduce the number of memory accesses required, the limited number of registers in the 8085 microprocessor can restrict the amount of data that can be manipulated at any given time.
Complex addressing modes: The addressing modes used in the data transfer instructions can be complex, which can make programming more difficult.
Limited I/O port access: The 8085 microprocessor has a limited number of input/output ports, which can restrict the amount of data that can be transferred to external devices.
Limited data size: The 8085 microprocessor uses 8-bit data transfer instructions, which can limit the amount of data that can be transferred in a single instruction. This can be a disadvantage for applications that require large amounts of data to be transferred.
Applications :
Data processing: The data transfer instructions in the 8085 microprocessor are used to transfer data between registers and memory locations. This allows the microprocessor to manipulate and process data in various ways, such as moving data, copying data, and swapping data.
Input/output operations: The data transfer instructions are used to transfer data between the microprocessor and input/output devices such as sensors, displays, and other peripherals. This enables the microprocessor to receive input data and send output data to external devices.
Memory management: The data transfer instructions are used to manage memory in the microprocessor. This includes loading programs and data into memory, moving data between different memory locations, and allocating memory for different tasks.
Interrupt handling: The data transfer instructions are used in interrupt handling to save the current state of the microprocessor and transfer control to an interrupt service routine. This involves transferring the contents of various registers and memory locations to a stack or other memory location.
Communication systems: The data transfer instructions are used in communication systems to transfer data between the microprocessor and external devices such as modems, network interfaces, and other communication devices.
Similar Reads
Microprocessor Tutorials
A microprocessor is fabricated on a single integrated circuit (IC) or chip that is used as a central processing unit (CPU). It is used as an electronic device, giving output instructions and executing data. In the microprocessor tutorial page, We will cover some basic topics like the introduction to
9 min read
Introduction of Microprocessor
In this article we will go through the Microprocessor, we will first define what is a Microprocessor, then we will go through its different types with its block diagram and we will see different types of processors, At last, we will conclude our article with some applications and FAQs.What is Microp
6 min read
Types of Microprocessors
This article provides an overview of the microprocessor, one of the most important components of a modern computing device. It describes how they function like the "brain" of the computer and enumerates the different types of Microprocessors. This also includes the vector processors, array processor
6 min read
Microprocessor | Intel x86 evolution and main features
Intel x86 architecture has evolved over the years. From a 29, 000 transistors microprocessor 8086 that was the first introduced to a quad-core Intel core 2 which contains 820 million transistors, the organization and technology have changed dramatically. Some of the highlights of the evolution of x8
5 min read
Evolution of Microprocessors
Transistor was invented in 1948 (23 December 1947 in Bell lab). IC was invented in 1958 (Fair Child Semiconductors) By Texas Instruments J Kilby. The first microprocessor was invented by INTEL(INTegrated ELectronics). Size of the microprocessor - 4 bit NameYear of InventionClock speedNumber of trans
5 min read
Architecture of 8085 microprocessor
A microprocessor is fabricated on a single integrated circuit (IC) or chip that is used as a central processing unit (CPU).The 8085 microprocessor is an 8-bit microprocessor that was developed by Intel in the mid-1970s. It was widely used in the early days of personal computing and was a popular cho
11 min read
Pin diagram of 8085 microprocessor
The 8085 microprocessor is a popular 8-bit microprocessor developed by Intel. It has 40 pins, each with a specific function for interfacing with memory, input/output devices, and other components.Pin diagram of 8085 microprocessor is shown below: Key Pin Descriptions1. Address Bus and Data BusAddres
5 min read
Registers of 8085 microprocessor
Introduction : A microprocessor is a multipurpose, programmable, clock-driven, register-based electronic device that reads binary instructions from a storage device called memory, accepts binary data as input and processes data according to those instructions and provide results as output. A 8085 mi
8 min read