What is a register pair?

What is a register pair?

To hold data of 16-bit a combination of two 8-bit registers can be employed. The combination of two 8-bit registers is called register pair. The valid register pairs in the 8085 are: D-E, B-C and H-L. The H-L pair is used to act as a memory pointer.

What are the register pairs in Intel 8085?

The 8085 has six general-purpose registers to store 8-bit data; these are identified as- B, C, D, E, H, and L. These can be combined as register pairs – BC, DE, and HL, to perform some 16-bit operation.

What is a register explain?

Registers are a type of computer memory used to quickly accept, store, and transfer data and instructions that are being used immediately by the CPU. The registers used by the CPU are often termed as Processor registers.

What is CMC in microprocessor?

Microprocessor8085. In 8085 Instruction set, CMC stands for “CoMplement the Carry flag”. It performs complement operation on the cy flag, and the result is stored back in the cy flag.

What is the use of B register?

The “B” Register To quickly and easily multiply or divide A by another number, you may store the other number in “B” and make use of these two instructions. Apart from using MUL and DIV instructions, the “B” register is often used as yet another temporary storage register, much like a ninth R register.

Why accumulator is called special register?

The accumulator takes a value in, operates on it and puts the value out; it could be stored in short term memory, stored in longer term memory, written to an output port or other peripheral. What comes out of the accumulator is effectively the processors reason for existence which makes it pretty special.

What is accumulator register in assembly language?

An accumulator is a type of register included in a CPU. It acts as a temporary storage location which holds an intermediate value in mathematical and logical calculations. Intermediate results of an operation are progressively written to the accumulator, overwriting the previous value.

What is register English?

Register often refers to the degree of formality of language, but in a more general sense it means the language used by a group of people who share similar work or interests, such as doctors or lawyers. Teachers often divide functional language into three working categories, formal, neutral and informal.

What is CLD instruction?

Description. The cld instruction clears the direction flag: DF = 0. The direction flag (DF) is used to influence the direction in which some of the instructions work when used with the REP* prefix. There is a number of instructions that are influenced by this flag directly, for example MOVS, LODS, SCAS.

What is the current content of HL and BC register pairs?

As It is 1-Byte instruction so it occupies a single Byte place in the memory. We are considering the initial content of HL and BC register pairs are 4050H and 4060H. So after 16-bit addition the current content of HL register pair will be 80B0H. The result of execution of this instruction is shown below with a tracing table.

How are registers used in a microprocessor?

They are used to store data temporarily during the execution of the program. For example, there is no instruction to add the contents of Band E registers. At least one of the operands has to be in A. Thus to add Band E registers, and to store the result in B register, the following have to be done.

Can a register be added to a B register?

Move to A register the contents of B register. Then add A and E registers. The result will be in A. Move this result from A register to B register. It is possible to use these registers as pairs to store 16-bit information. Only BC, DE, and HLcan form register pairs.

Can a function be used for two other registers together?

This function cannot be be used for two other registers together – the addition has to be performed with the accumulator being one of the addends. Thus, for example, the contents of, say, register C cannot be summed up directly to the contents of register B.