Question

Explain how the program is working each line please. Thanks,

Given the following program, what is the value of the SP after the program execution? text .global STRT mov.w #0x300,SP STRT StopWDT mov.w #WDTPW+WDTHOLD,WDTCTL push R6 jmp ed ed

Answer 1

Answer in the comments below:

.text ; This is the assembler directive indicating the beginning of program in the flash memory

.global _STRT ; .global is also as assembler directive. It makes the assembly language module titled ;STRT available to linker. This, in turn, allows other programs to use it if needed

STRT mov.w #0x300,SP; This initializes the stack pointer to RAM address 300 hex

StopWDT mov.w #WDTPW+WDTHOLD, WDTCTL ; This stops the watch-dog timer

push R6 ; This decrements SP by two and then pushes the contents of register R6 on to the stack. If ;this program is for MSP430 family then stack pointer would be decremented to 0x28E and then the two ;bytes of R6 would be stored on the RAM locations pointed by SP.

ed jump ed; This is an infinite loop. The program keeps executing this loop till it MCU receives a reset or an interrupt. Effectively this is a halt instruction.

Hope this helps