This behavior is seen in the case of interrupt handling. Now it can be seen from the 1st and the 4th instructions, that the control flow was not sequential and the value of PC was stored in the memory, so that the control can again come back to the address where it left the execution. The 4th instruction places the value of MBR ( which was the old PC value) into Memory. The 3rd instruction places an address Y into PC. The 2nd instruction places an address X into MAR. The 1st instruction places the value of PC into MBR PC - Program Counter ( It contains the address of the instruction being executed at the current time ) MAR - Memory Address Register ( that holds the memory location of data that needs to be accessed.) MBR - Memory Buffer Register ( that stores the data being transferred to and from the immediate access store) ISRO CS Syllabus for Scientist/Engineer Exam.ISRO CS Original Papers and Official Keys.GATE CS Original Papers and Official Keys.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |