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The processor Motorola 68000 operates in one of two privilege modes of privilege: the "Supervisor" mode and the "User" mode. The privilege mode determines:* which instructions are legal:** user programs are not permitted to execute the stop These modes control system access, instruction or the reset instruction** to ensure that a user program cannot enter the Supervisor mode except in a controlled mannerexecution, the instructions which modify the whole state register are privileged** to aid in debugging programs which are to be used as operating systems, the move to user stack pointer (MOVE to USP) and move from user stack pointer (MOVE from USP) instructions are also privileged* select between the Supervisor Stack Pointer (SSP) and the User Stack Pointer (USP) in instruction references* and may by used by an external Memory Management Unit (MMU) to control and translate memory accessesmanagement.

All exception processing is done in the Supervisor In User mode, regardless of the setting of the S bitprivileged instructions like STOP, RESET, and status register modifications are prohibited. The bus cycles generated during exception processing Debugging-related instructions (MOVE to/from USP) are classified as supervisor referencesrestricted to Supervisor mode. All stacking operations during exception processing use the The processor uses separate stack pointers: Supervisor Stack Pointer(SSP) and User Stack Pointer (USP), ensuring system integrity.

An external Memory Management Unit (MMU) can enforce access control based on privilege levels. All exceptions trigger Supervisor mode, using the SSP for stack operations and classifying bus cycles as Supervisor references. By enforcing a clear separation between User mode and Supervisor modemodes, the 68000 architecture provides:*System system ensures security by preventing unauthorized execution of privileged operations*Stability , maintains stability by ensuring that keeping user programs cannot interfere with from disrupting the operating system*Support for multitasking OS, and memory protection when integrated supports multitasking with an MMUenhanced memory management.