Embedded System - Quiz

In embedded systems, the algorithmic level simulates the algorithms used within the system. This level involves designing and testing algorithms and optimizing them for implementation in the final embedded system. The algorithmic level is an important stage in the design process that ensures the embedded system performs its intended function accurately and efficiently.

MESI is a cache coherency protocol that supports a shared state. It is a mechanism for maintaining cache consistency between multiple processors in a shared-memory system. The acronym MESI stands for Modified, Exclusive, Shared, and Invalid, which are the possible states that a cached copy of a memory block can be in. The protocol uses bus snooping techniques to detect changes in shared memory, ensuring that the data in the caches of all processors is consistent.

The external interrupts are a common method for connecting peripherals to the processor. These interrupts are provided through the external pins connected to the peripherals, allowing them to communicate with the processor.

In software interrupts, the different modes of operation, such as user mode and supervisor mode, provide data protection. This mechanism allows memory, associated code, and data to be protected from each other.

In the MC68HC11 microcontroller, multiplying two 8-bit values requires a 16-bit register. Therefore, the command for multiplying is an 8-bit command.

The primary function of an accumulator is to store intermediate results during arithmetic and logical operations. It is a register in the processor that can hold a single value at a time and can be used for various operations, including addition, subtraction, multiplication, and logical operations.

The stack is an area in memory used for temporary storage of data, especially during function calls. It is a short-term, large-scale storage area.

The processor behind the IBM PC AT is 80286, which was a successful processor in the PC market.

The four general-purpose 16-bit registers in Intel 80286 are AX, BX, CX, and DX. Additionally, there are four segmented registers, two index registers, and a base pointer register.

The 80286 processor can access memory beyond 1MB by using a paging mechanism and special hardware to simulate the missing address lines. This technique is known as expanded memory, and it allows applications to utilize additional memory beyond the 1MB limit of real mode.