Embedded systems memory management MCQ Quiz – Objective Question with Answer for Embedded systems memory management

The descriptor privilege level is used to restrict access to the segment which helps in the protection mechanism. It acquires two bits of the descriptor.

The S bit determines whether it is a system segment or a normal segment. When the S bit is set, it might be a code segment or a data segment. If the S bit clears, it is a system segment.

The memory protection unit in the ARM architecture divides the memory into eight separate regions. Each region can be small as well as big ranging from 4 Kbytes to 4 Gbytes.

The memory region possesses three bits which are the cacheable bit, bufferable bit, and access permission bit.

In the ARM protection architecture, the memory is divided into some regions of sizes 4 Kbytes to 4 Gbytes. These regions possess bits called the cacheable bit, buffer bit, and access permitted bits. The regions are numbered as per priority level for which the permission bits take precedence if any of the regions get overlapped.

The ARM architecture memory protection unit divides the memory range into different regions of size ranging from 4 Kbytes to 4 Gbytes. Each region is associated with certain bits called the cacheable bit, buffer bit, and access permitted bit. These bits are similar to the permission bit in the ARM memory management unit architecture which is stored in the control register.

The cacheable bit and the buffer bit are used to control the behavior of the cache. Depending on the cacheable bit and the buffer bit, the memory access will complete successfully.

The memory management unit and the memory protection unit provide security to the processor by trapping the invalid memory accesses before they corrupt other data.

The memory protection unit allows a tripped memory down memory management unit in which the memories are partitioned and protected without any address translation. This can remove the time consumption in the address translation thereby increasing the speed.

The memory protection unit has many advantages over the other units. It can reduce the chip size, cost, and power consumption.

The memory management unit can be used as a protection unit by disabling the address translation that is, the physical address and the logical address are the same.

If memory access from the software does not access the correct data, an error signal is generated which will start a supervisor-level software for the decision.

Different tasks assign their own address space and whenever a task access memory outside its own address space, a segmentation fault result and which in turn results in the termination of the offending application.