How can you use the stos instruction?

Question

assembler

Friends, help me deal with such an instruction as stos, how can I transfer this (the value from ax to the first variable):
mov first, ax
And then put the first value back into ax (as I understand it, the usual mov is also possible here):
mov ax, first

Answer 1

By setting the value of the registers es:dito the address of your variable. But the question is out of touch with reality. This thing is used to process arrays in a loop, because it itself moves the pointer to the next element.