Why are jumps so important in our assembly code?
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Why are jumps so important in our assembly code?
Jumping is somewhat useful for skipping over bad code, but it really gets useful when you add conditional jumps. These are used after a “cmp” instruction to compare two values. (Seriously!?) There are also “n” NOT versions for each jump; for example “jno” jumps if there is NOT overflow.
Why is assembly code important?
The learning of assembly language is still important for programmers. It helps in taking complete control over the system and its resources. By learning assembly language, the programmer can write the code to access registers and retrieve the memory address of pointers and values. It is cryptic and symbolic language.
How does jump instruction work?
Jump Instruction The jump instructions load a new value into the PC register, which stores the value of the instruction being executed. This causes the next instruction read from memory to be retrieved from a new location.
What is Jump Range 8051?
The relative address ranges from 00H to FFH which is divided into forward and backward jumps; that is, within –128 to +127 bytes of memory relative to the address of the current PC (program counter).
Conditional jump instructions – signed
| Instruction | Alternative | Action |
|---|---|---|
| JLE | JNG | Jump if sign and overflow flags are different and zero flag is set (jump if “less or equal” or “not greater”) |
| JLNE | JG | Jump if sign and overflow flags are the same and zero flag is clear (jump if “not less or equal” or “greater”) |
Why do you need conditional and unconditional jump?
Unconditional Jump Instructions: Transfers the program sequence to the described memory address. Conditional Jump Instructions Transfers the program sequence to the described memory address only if the condition in satisfied.
What is the purpose of the jump instruction after the consequent?
At the end of the consequent, a jump is executed to skip the alternative. A jump instruction is used to inform the CPU to go directly to another address, skipping any intervening instructions.
What is the purpose of branching instruction?
The branch instructions are used to change the sequence of instruction execution. Use branch instructions to change the sequence of instruction execution.
What is jump instruction in microcontroller?
Jump if bit = 1 and clear bit. JZ (jump if A = 0) − In this instruction, the content of the accumulator is checked. If it is zero, then the 8051 jumps to the target address. JZ instruction can be used only for the accumulator, it does not apply to any other register.