Table of Contents
What is the function of Dad instruction in 8085 microprocessor?
In 8085 Instruction set, DAD SP instruction is a special case of DAD rp instruction. In this instruction contents of HL and SP will get added and sum thus produced will get stored onto HL register pair. It occupies only 1-Byte in memory.
What are the machine cycles in the 8085 microprocessor?
Machine Cycle in 8085 Microprocessor
| S No | Instruction | Machine cycle – 1 |
|---|---|---|
| 1 | MOV A,B | OF |
| 2 | MVI A, 50H | OF |
| 3 | LDA 5000H | OF |
| 4 | STA 5000H | OF |
How many machine cycles are there in 8085?
How many machine cycles does 8085 have, mention them? In 8085 have 9 machine cycles, they are opcode fetch, memory read, memory write, I/O read, I/O write,Interrupt acknowledge, halt, hold & reset.
What is RST microprocessor?
RST stands for Restart instructions Explanation: In 8085 microprocessors. RST stands for Restart instructions.
What is idle cycle bus 8085?
The opcode fetch cycle takes 4 T states and the remaining 6 T states, divided into two Machine Cycles, are for the instruction execution. During these 6 T (two Machine Cycles) states no bus operations are performed. Hence they are called bus idle Machine Cycles.
What is LXI in COA?
We can use this instruction to load data from memory location using the memory address, which is stored in the register pair rp. For an example, if the instruction is LXI H, FE50. It means that the FE50 is loaded into the HL register pair.
What is bus idle machine cycle?
A bus idle machine cycle is a cycle during which the Data bus of the microprocessor is not in use. That is the Data bus is in IDLE state. When the Bus idle machine cycle takes place, the following events can be observed. No wait cycles are possible. No memory or I/O device communicates with the microprocessor.
What is an instruction cycle in microprocessor?
The instruction cycle (also known as the fetch–decode–execute cycle, or simply the fetch-execute cycle) is the cycle that the central processing unit (CPU) follows from boot-up until the computer has shut down in order to process instructions.
What is machine instruction cycle?
The machine instruction cycle describes the order that instructions are processed in a computer. Instructions are processed under the direction of the control unit in a step-by-step manner.
What is restart instruction?
In 8085 Instruction set, RSTn is actually standing for “Restart n”. And in this case, n has a value from 0 to 7 only. Thus the eight possible RST instructions are there, e.g. RST 0, RST 1, …, RST 7. They are 1-Byte call instructions.
What is PCHL instruction?
PCHL: it loads the program counter with HL data. the content of H placed into higher order byte and L placed at low order bytes.