What is the instruction set of 8051?
An 8051 Instruction consists of an Opcode (short of Operation – Code) followed by Operand(s) of size Zero Byte, One Byte or Two Bytes. The Op-Code part of the instruction contains the Mnemonic, which specifies the type of operation to be performed.
What are the logical instructions in 8051?
List of logical instructions in 8051
| Operation | Mnemonics | Description |
|---|---|---|
| XOR | XRL Address, #data | [Data at Address]<-[Data at Address] XOR [Data] |
| Clear | CLR A | [A]<-0 |
| Complement | CPL A | [A]<-[A]’ |
| Rotate left | RL A | Shifts the value in accumulator to the left |
What is Acall instruction?
The ACALL instruction calls a subroutine located at the specified address. The PC is incremented twice to obtain the address of the following instruction. The subroutine that is called must be located in the same 2KByte block of program memory as the opcode following the ACALL instruction.
What is the purpose of Setb instruction?
The SETB instruction sets the bit operand to a value of 1. This instruction can operate on the carry flag or any other directly addressable bit.
How many types of instruction sets are there?
Following are the instruction set architectures: Reduced Instruction Set Computer (RISC) Complex Instruction Set Computer (CISC) Minimal instruction set computers (MISC)
Which instruction is used to perform operations in 8051?
The ANL instruction performs a bitwise logical AND operation between the specified byte or bit operands and stores the result in the destination operand. When this instruction is used to modify an output port, the value used as the port data will be read from the output data latch, not the input pins of the port.
What is Acall and Lcall instruction?
ACALL (Absolute Call) ACALL is a 2-byte instruction, in contrast to LCALL which is 3 bytes. The difference between the ACALL and LCALL is that the target address for LCALL can be anywhere within the 64K-bytes address space of the 8051, while the target address of CALL is within a 2K-byte range.
What is range of Acall and AJMP instructions?
ACALL allows you to jump to a subroutine within the same 2K page. LCALL allows you to jump to a subroutine anywhere in the 64K code space. The advantage of ACALL over LCALL is that it is a 2-byte instruction while LCALL is a 3-byte instruction. Calling range.
What is the use of swap instruction in 8051?
The SWAP instruction exchanges the low-order and high-order nibbles within the accumulator. No flags are affected by this instruction.
What is the difference between Lcall and Acall instructions?
ACALL is a 2-byte instruction, in contrast to LCALL which is 3 bytes. The difference between the ACALL and LCALL is that the target address for LCALL can be anywhere within the 64K-bytes address space of the 8051, while the target address of CALL is within a 2K-byte range.
What are the instructions in the 8051 instruction set?
8051 Instruction Set An instruction is a command given to the microcontroller for performing a specified operation on presented data. The instruction set of microcontroller is a collection of instructions that the microcontroller is designed to execute. Data moving or handling Instructions:
Is the 8051 microcontroller an 8 bit processor?
As the 8051 family of Microcontrollers are 8-bit processors, the 8051 Microcontroller Instruction Set is optimized for 8-bit control applications. As a typical 8-bit processor, the 8051 Microcontroller instructions have 8-bit Opcodes.
How many addressing modes are there in the 8051?
An Addressing Mode is a way to locate a target Data, which is also called as Operand. The 8051 Family of Microcontrollers allows five types of Addressing Modes for addressing the Operands.
When does 8051 jump to the target address?
Consider the instruction DJNZ register; label is used for performing a loop operation. In this instruction, the register is decremented by 1; if this is not zero, then 8051 jumps to the target address referred by the label.