※ 引述《bigpiku (屁屁外星人)》之铭言：
: 很难ㄇ
: 文组ㄑ上会不会死掉??
: 窝优点害怕..
: 而且ㄊ跟fortran充堂惹
: 还是就ㄑ上fortran就好QAQ??
In common cases, we write programs running above operating systems.
But embedded systems, under some kinds of definitions,
do not contain an OS, which means you have to manage registers and
memory carefully.
And all I/O and interrupts have to be handled by programmers themselves.
This requires knowledge about digital system,
computer architecture and sometimes operating systems (because
some hardware-level topics are also discussed in this subject).
And skill of C language is necessary, of course.
But sometimes there are still some teachers not requiring this.
They teach those knowledge in their own class.
So you should ask your teacher, TAs or who studied that course.
There does not exist an absolutely exact anwser to your question.