21. Which of the following helps in reducing the energy consumption of the embedded system?
a) emulator
b) debugger
c) simulator
d) compilers
Answer: d
The compilers can reduce the energy consumption of the embedded system and the compilers performing the energy optimizations are available.
22. What is the purpose of the memory refresh register of Z80?
a) To control on-chip SRAM
b) To control on-chip DRAM
c) To clear cache
d) To control ROM
Answer: b
In addition to the general-purpose registers, a stack pointer, program counter, and two index registers are included in Z80. It was also used in many embedded designs because of its high-quality performance and for its in-built refresh circuitry for DRAMs.
23. What does MESI stand for?
a) modified exclusive system input
b) modifies embedded shared invalid
c) modified exclusive shared invalid
d) modified exclusive stale invalid
Answer: c
The MESI protocol supports a shared state which is a formal mechanism for controlling the cache coherency by using the bus snooping techniques. MESI refers to the states that cached data can access. In the MESI protocol, multiple processors can cache shared data.
24. Which of the following is the pin efficient method of communicating between other devices?
a) memory port
b) peripheral port
c) parallel port
d) serial port
Answer: d
The serial ports are considered to be the pin efficient method of communication between other devices within an embedded system.
25. Which of the following is a traditional method for emulating the processor?
a) CPU simulator
b) SDS
c) ICE
d) Low-level language simulator
Answer: c
The SDS is one of the simulation tools used in embedded systems. CPU simulator and the low-level simulator are the other kinds of simulators used in the embedded system design.
26. Which of the following unit protects the memory?
a) memory management unit
b) peripheral unit
c) execution unit
d) bus interface unit
Answer: a
The resources have to be protected in an embedded system and the most important resource to be protected is the memory which is protected by the memory management unit through different programming.
27. Identify the standard software components that can be reused in an embedded system design?
a) memory
b) application software
c) application manager
d) operating system
Answer: d
There are certain software components that can be reused in an embedded system design. These are the operating systems, real-time databases, and some other forms of middleware.
28. What does ICE stand for?
a) in-circuit EPOM
b) in-code emulation
c) in-circuit emulation
d) in-code EPROM
Answer: c
The ICE or in-circuit emulation is one of the traditional methods used to emulate the processor in the embedded system so that the software can be downloaded and can be debugged in situ in the end application.
29. Who proposed the first power model?
a) Tiwari
b) Russell and Jacome
c) Russell
d) Jacome
Answer: a
Tiwari proposed the first power model in the year 1974. The model includes the so-called bases and the inter-instruction instructions. Base costs of the instruction correspond to the energy consumed per instruction execution when an infinite sequence of that instruction is executed. Inter instruction costs model the additional energy consumed by the processor if instructions change.
30. Which of the following offers external chips for memory and peripheral interface circuits?
a) Embedded system
b) Peripheral system
c) Microcontroller
d) Microprocessor
Answer: d
Microcontrollers are the CPUs that have integrated memory and peripherals whereas microprocessor offers external chips for memory.
