What is BLX instruction in ARM?

What is BLX instruction in ARM?

The BLX instruction copies the address of the next instruction into LR ( R14 , the link register). The BLX instruction can change the instruction set. BLX label always changes the instruction set. It changes a processor in ARM state to Thumb state, or a processor in Thumb state to ARM state.

What is LDR in ARM?

Usage. The LDR pseudo-instruction is used for two main purposes: to generate literal constants when an immediate value cannot be moved into a register because it is out of range of the MOV and MVN instructions. to load a program-relative or external address into a register.

What do ARM subs do?

The SUB instruction subtracts the value of Operand2 or imm12 from the value in Rn . In certain circumstances, the assembler can substitute one instruction for another.

What is BX in ARM?

bx stands for branch and exchange instruction set Which means that according to the lsb (least significant bit) of the address to branch to, the processor will treat the next instruction as ARM or as thumb.

What does bl mean in assembly language?

Branch Link (BL) performs a similar operation, but it copies the address of the next instruction into R14, the link register (LR).

What is bl in ARM?

ARM uses the branch and link instruction (BL) to call a function and moves the link register to the PC (MOV PC, LR) to return from a function.

What is bl in arm?

What does BX LR do?

In BX instructions, the LSB of the value contained in the register determines the next state (Thumb/ARM) of the processor. With these instructions, the return address will be stored in the link register (LR) and the function can be terminated using BX LR, which causes program control to return to the calling process.

What is ADC in ARM?

Analog to Digital Converter(ADC) is used to convert analog signal into digital form. LPC2148 has two inbuilt 10-bit ADC i.e. ADC0 & ADC1. ADCs in LPC2148 use Successive Approximation technique to convert analog signal into digital form.

What does BX LR do assembly?

What does BX instruction do?

The BX instruction causes a branch to the address contained in Rm and exchanges the instruction set, if required: BX Rm derives the target instruction set from bit[0] of Rm : If bit[0] of Rm is 0, the processor changes to, or remains in, ARM state.