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The correct answer is (a) 1

For explanation: Any VARIABLE declared ‘const’ at any point in a program will never be able to change it’s value THROUGHOUT the COURSE of the program. So, the programmer has to be careful to put in the APPROPRIATE correct value into the variable before declaring it as ‘const’.

The correct answer is (a) Yes

Easy explanation: Any GLOBAL variable when defined in a PROGRAM automatically is open for all functions present in the program to access and perform read or WRITE OPERATIONS. On the contrary any variable defined within the SCOPE of a function, will only be able to be accessed within the function itself.

Right answer is (a) replace()

BEST explanation: The replace FUNCTION works with 3 arguments; the index in the SOURCE string, the string to be substituted with, and the string variable. It can be USED as “str.replace(a,b, “hello”);” where ‘b’ characters are REPLACED from index ‘a’ in ‘str’.

Correct CHOICE is (a) 0

The explanation: The back() FUNCTION returns a character from the string given as input. It takes in no arguments. It returns the last character that is PRESENT in the string. It can be USED as “cout<

The correct answer is (a) 1

For EXPLANATION: The analogRead() function is used to take analog signal inputs to the Arduino. It requires 1 argument; the PIN number which WOULD indicate which pin is to be used for that particular OPERATION. This will make the Arduino to start reading voltage fluctuations of the ORDER of 0V to 5V or 3.3V for some Arduino Boards.

The correct option is (b) Yes, it can, but only on certain ARDUINO BOARDS

The explanation: The pins in the Arduino Boards are all DIGITAL by default. The analog functionality is an addon to the board with the help of an ADC (Analog to Digital Convertor) Circuit, or a DAC (Digital to Analog Convertor) Circuit. Thus, all analog pins SUPPORT digital IO but not all digital pins support analog IO. However, this is an exception in the Arduino Nano, Mini and Pro Mini.

The correct choice is (a) 2

For explanation I would say: The ARDUINO subfolder of the Hardware section CONTAINS support for 2 architectures; AVR and SAM. The AVR Microcontrollers are included in the most common Arduino BOARDS like the Uno, Nano, Mega, etc. However, some Arduino Boards like the Arduino Due don’t use AVR but use the SAM 32-bit ARM PROCESSORS.

Right choice is (B) INPUT and OUTPUT

The best I can explain: The pinMode() method determines whether the pin number given in the code is to be USED as an input pin WHEREIN it can read voltage from an external CIRCUIT or for setting a particular voltage at the pin output to be plugged to an external circuit.

The correct answer is (c) 3

For EXPLANATION: The constrain() FUNCTION is used to restrict the output from going below or above a certain minimum or maximum number respectively. It takes THREE ARGUMENTS; the number to be contrained, the minimum value, and the maximum value.

The correct choice is (a) Arduino MKR 1010

The explanation: The library enables the Wi-Fi CAPABILITIES of the Arduino MKR 1010 BOARD. It can be also used as a server to ACCEPT incoming connections and EVEN send outgoing requests. It also supports WEP and WPA2 Encryption Systems.

Right answer is (c) Audio.h

Explanation: The ARDUINO Due uses the Audio.h library for manipulation of sounds. It allows the Arduino Due to USE the DAC0 and DAC1 pins to open .wav audio files from a source. Most of the time this library is used with the SD.h standard library to enable the Arduino Due to be able to READ audio files from SD Cards.

Right CHOICE is (a) Connecting to the INTERNET over GSM

Explanation: The MKRNB LIBRARY runs on the Arduino MKR NB 1500 and helps in connecting the board to the internet via GSM. The board CONSISTS of a modem that takes the data from the serial port of the board and then sends it to the internet via the GSM Network with the help of AT commands.

Right OPTION is (a) The output is padded with zeros

For explanation I would say: If the value PASSED as an argument to the ANALOGREADRESOLUTION() function is higher than the physical capability of that PARTICULAR board’s ADC, then the output is padded with zeros so as to enable other boards EQUIPPED with ADC’s having higher resolutions can process the data.

Right answer is (a) ENABLE Verbose Output

To elaborate: A verbose is a feature that reports all information in a PROCESS, function or code. The Arduino Verbose Output helps in displaying the output for each EXECUTION STEP in the Arduino Compilation Process.

The correct option is (a) AVR-G++/GCC

Easy explanation: The AVR-GCC/G++ software is a compiler which can TAKE C/C++ CODE as INPUT and translate or compile it into Binary Code that FOLLOWS the instruction set for the AVR Microcontrollers. They’re used in the Arduino software since most Arduino Boards USE the AVR Microcontroller family.

Right answer is (C) sketches

The explanation is: Any Arduino CODE that is saved using the Arduino IDE, is referred to as a “sketch” by the Arduino IDE. These “sketches” are NOTHING but the code saved in a file with the extension name being “.INO”.

Right choice is (b) No

The explanation: The ARDUINO code uses a lot of pre-built libraries that are specific to the Arduino PLATFORM and would CERTAINLY not work on any other platform. However, one can remove the lines of code containing the prebuilt libraries from their code and use the code to run on any other C++ platform performing other minor MODIFICATIONS to the code, SINCE the original Arduino code is after all based on C++.

The CORRECT choice is (a) To find the datatype of the variable

Explanation: The typeid() function returns the datatype of the expression or variable that is PASSED through it. It returns a constant type_info OBJECT which can be used as a STRING in further programming.

Correct answer is (a) To FIND the SINE of a number

To explain: The sin() function is used to find the sine of a number. It takes ONE argument; the number whose sine is to be found out. This number is to be entered in the RADIAN format and not the degree format. This function can accept the float datatype and gives the output in the double datatype.

The correct answer is (b) 2’s Complement

To elaborate: The int DATATYPE STORES 16 bits of data. The way it handles negative numbers is by a method called the 2’s complement WHEREIN a sign bit is added to the binary equivalent of the number and then all the bits are INVERTED and then added by one.

Correct ANSWER is (b) No

Explanation: The delay() function is USED to suspend OPERATIONS for a specified amount of time. This is really handy for certain operations like viewing data on the SERIAL Monitor. However, this has a very serious drawback; it suspends ALL operations during this time, i.e. no mathematical calculations, no sensor data INPUTS, etc. for the time it is in effect.

Correct answer is (a) Yes

The explanation: Infinite loops are a good way to ensure that your PROGRAM is running continuously WITHOUT any interruptions. However in programming languages that allow raw memory MANAGEMENT, it’s very easy to have a memory leak, or a continuous allocation of memory which eventually leads to the programming using all the memory AVAILABLE and eventually crashing the ENTIRE system.

Right answer is (c) 4 Microseconds

Easiest explanation: The micros() function gives the up-time of the Arduino program in microseconds. This function has a resolution, i.e. the intervals in which it gives an output. This resolution DEPENDS on the FREQUENCY of the specific Arduino Board that its RUNNING on. On the Arduino Duemilanove it’s resolution is 4 Microseconds.

Correct choice is (c) To allow for parallel execution of FUNCTIONS

Easiest explanation: The Scheduler Library works only on the ARDUINO ZERO, Due, etc. and other Arduino Boards having SAM and SAMD architectures. It allows for parallel running of functions without using interrupt. It allows the CPU to switch seamlessly between TASKS.

The correct answer is (a) SPI

Explanation: The SD.h library for COMMUNICATION between SD Card Modules and Arduinos use SPI (Serial Peripheral Interface) for ESTABLISHING communications. The SPI is a synchronous Serial Communication Protocol which is USED for short distance communications between microcontrollers and devices like SD Card READERS, shift RESISTORS, etc.

The correct ANSWER is (d) Yes, it can, but only through certain pins

The BEST explanation: The pins in the Arduino Boards are all digital by default. The analog functionality is an addon to the BOARD with the HELP of an ADC (Analog to Digital Convertor) Circuit which is only connected to a certain number of digital pins, so therefore not all pins can SUPPORT analog communications.

The correct answer is (b) To change the analog signal reference value

The explanation: The ANALOGREFERENCE() function changes the value of the internal reference voltage for all analog CALCULATIONS in the Arduino Board. For the function to work properly we need to supply the desired voltage LEVEL to the AREF pin on the Arduino Board physically before invoking the function. However, any voltage GREATER than 5V is not recommended since it can DAMAGE the board.

The correct ANSWER is (a) Yes

To explain: The LOOP function is a custom PREDEFINED function that was designed to execute code over and over again for the Arduino. However if a programmer can replicate that same functionality in his/her code without the USE of the loop() function then there is compulsion for him/her to INCLUDE the loop() function in the program.

Right answer is (a) AVRDUDE

The best I can explain: The AVR-GCC/G++ software is a compiler which can take C/C++ code as input and TRANSLATE or compile it into BINARY Code that follows the instruction set for the AVR MICROCONTROLLERS. After that process is done, the avrdude software has the job of uploading the hex file to the microcontroller, more specifically the AVR Microcontroller family.

The CORRECT choice is (b) No

Best explanation: The Arduino language is a modified version or subset of the C++ PROGRAMMING language. Hence EVEN if the C++ programming language is a general-purpose programming language, due to the inclusion of certain SPECIFIC libraries in the subset, the Arduino code cannot run on any other embedded system other than another Arduino BOARD, thus making the programming language platform specific.

Right choice is (B) Editor->Preprocessor->Compiler

The best I can explain: The code that is written is FIRST DONE so with the help of the editor. WITHOUT the editor there will be no place where the programmer can write his or her code. After that the code is handed over to the preprocessor and finally the compiler which translates the code into the ARDUINO’s Assembly Instruction Set.

Correct option is (C) 2 bytes

For explanation I would say: The volatile keyword has a LOT of uses and advantages in programming. However, when it COMES to inputting large quantities of data, ANYTHING more than a bit in size will definitely result in the formation of garbage values. So, in order to input that kind of data we need to shut off all interrupts before inputting the VALUE.

Right ANSWER is (b) No

Easy explanation: The SIZE() and LENGTH() FUNCTIONS both return the number of characters that constitute the string given and can be USED interchangeably from a utilitarian standpoint. There is absolutely no difference between the two functions.

The correct answer is (b) The BREAK statement

To ELABORATE: From all the above options only the break statement is generally USED for exiting loops. This can be also applied for switch case control structures. The difference between the break statement and the exit statement is that the break statement can only ABORT looping control structures, but the exit statement completely aborts the program execution.

Correct choice is (d) Long

The best I can explain: Any NUMBER can be represented in the form of a whole number or a floating-point number. If it must be represented as a whole number, then there are many OPTIONS depending upon the size of the number in question. Here the number 2146492440 should be represented USING the long datatype since it has a range of -2147483648 to -2147483647.

Correct choice is (c) BITWISE XOR

For explanation I WOULD say: The ^ operator is used to perform a bitwise XOR operation on any two NUMBERS which serve as the operands. It performs an XOR operation on each bit starting from the most significant bit to the LEAST significant bit.

Right option is (b) Arduino Due

Easy explanation: The USBHost LIBRARY was developed for the Arduino Due. This library allows the Arduino Due to appear as a USB HOST and connect to external peripherals like the MOUSE and keyboard. HOWEVER this does not include device connected through USB Hubs.

Right answer is (B) .hex

The best explanation: The assembly instructions for the microcontroller is STORED in a hex file. This file contains the assembly instructions in hex format for the microcontroller to understand and execute. It is the binary executable file that ALLOWS us to execute the high-level C CODE on any microcontroller.

Right answer is (b) It enables the programmer to ACCESS all of Arduino’s core functionality

The explanation is: The Arduino.h file is not something that we encounter during the process of WRITING the code for the Arduino board because the preprocessor takes care of it before COMPILATION. However, it is a very important file without which we cannot access the Arduino’s features like GPIO IO, Analog IO, etc.

The correct choice is (d) Java

To EXPLAIN I would say: The Arduino code is primarily a subset of the C++ programming language. HOWEVER, the IDE (Integrated Development Environment) was WRITTEN in the Java programming language. An IDE is a software that provides primarily a graphical user interface for COMPILING and maintaining/editing code for a platform.

Right answer is (a) Globally DEFINED or static

Explanation: The PROGMEM Utility can only be USED for variables which have “public” access to the entire program and conversely can be accessed by anyone, or is a static VARIABLE, which means they NEED to be defined outside a function and be static or non-static, or if they are defined WITHIN any function, they need to be static.

Correct CHOICE is (a) sizeof()

Best explanation: The primary use of the sizeof() function is to RETURN the length or size of an element that is given to it. So, if this element is an array which is a collection of ELEMENTS, it will GIVE the NUMBER of elements present inside the array.

Correct answer is (C) F() Macro

To explain: The F() macro is USED for sending data, which is usually in the form of strings that are declared within the Serial.print() function which MEANS they are not to be stored ANYWHERE in the program but are to be printed onto the serial MONITOR, to the Flash Memory before it is printed.

Right answer is (a) The min() function

Explanation: The min() function takes in 2 arguments and outputs only 1 NUMBER. This function finds out the minimum of the 2 numbers that are entered as arguments to the function. This function is ESSENTIAL in SORTING techniques.

Right option is (a) Yes

The explanation: Iteration is the method of executing a SET of statements repeatedly with the use of looping control structures LIKE the for-loop, while-loop, do-while loop, etc. while recursion does the same THING but without USING any looping control structures. It uses function call statements.

Right answer is (c) 1000 milliseconds

The best I can explain: The default TIME limit is set to 1000 milliseconds before the setTimeout() will wipe the data from the BUFFER if no time limit is PROVIDED externally. This FUNCTION has no return data type, and can be invoked from a host of FUNCTIONS.

Correct answer is (d) Arduino Uno

The explanation: The ANALOGREADRESOLUTION() function is used to change the resolution of the ADC for READING a particular voltage and mapping it to the number set. The resolution of the ADC is the number of levels up to which the ADC can quantize the analog SIGNAL. The Arduino Uno is not CAPABLE of executing that COMMAND.