Microcontrollers Question & Answers June 5, 2021 By WatElectronics This article lists 90+ Microcontrollers MCQs for engineering students. All the Microcontrollers Questions & Answers given below include a solution and link wherever possible to the relevant topic. The microcontrollers used in almost all electronic devices, it is composed of two terms micro and controller, whereas micro means very small in size, and controller means a device that controls the operations of all the devices. The microcontroller consists of various components like memory, serial input/output ports, peripheral devices, timers, counters, and clock circuits, so the microcontroller is nothing but an on-chip computer where all the devices of the computer are embedded on a single chip. It can be used as an engine controller in automobiles, they are also used in washing machines, refrigerators, microwave ovens for controlling the temperature in the ovens, etc. The speed of the microcontrollers is relatively slow compared to microprocessors. The microcontrollers are classified into three types based on bits they are 8 bit, 16 bit, and 32-bit microcontrollers. The 8-bit microcontrollers are used to execute both arithmetic and logical operations, the 8051 and 8031 are examples of 8-bit registers. The microcontrollers are of two types based on instruction set they are Reduced Instruction Set Computer, and Complex Instruction Set Computer. 1). The microcontrollers are used in ____________ Computers, laptops, televisions Printers, refrigerators Microwave owens All of the above None Hint Read more about 8051 Microcontroller 2). The speed of the microcontrollers are ___________ High Slow Very high Better None Hint 3). How many of microcontrollers are there based on bits? One Two Three Four None Hint 4). The microcontrollers based on memory classified into ______ 8 bit, 16 bit, 32 bit Embedded memory, external memory RISC, CISC All of the above None Hint 5). How many of microcontrollers are there based on instruction set? One Two Three Four None Hint 6). The 8-bit microcontrollers are used to execute _________ Arithmetic operations only Logical operations only Both a and b None of the above None Hint 7). ____________ is an example of 16 bit microcontroller 8031 microcontroller 8051 microcontroller 8096 microcontroller None of the above None Hint 8). The 32 bit microcontroller used in automatically controlled applications like __________ Automatic operational machines Medical appliances Both a and b None of the above None Hint 9). The type of microcontroller is designed in such a way that they don’t have a program memory on the chip is called as __________ External memory microcontroller Embedded memory microcontroller Both a and b None of the above None Hint 10). _________ is an example of external memory microcontroller Intel 8031 microcontroller 8051 microcontroller 8096 microcontroller None of the above None Hint 11). In embedded memory microcontroller has __________ Programs, data Counters, timers Input/Output ports All of the above None Hint 12). __________ is an example of embedded memory microcontroller Intel 8031 microcontroller 8051 microcontroller 8096 microcontroller None of the above None Hint 13). ___________ instruction set allows the user to insert a single instruction as an alternative to many simple instructions Reduced instruction set computer Complex instruction set computer Both a and b None of the above None Hint 14). The reduced instruction set computer reduces the operational time by shortening the clock cycle per instruction True False None Hint 15). _____________ is the first microcontroller designed by intel Intel 8031 microcontroller 8051 microcontroller 8096 microcontroller None of the above None Hint 16). The 8051 microcontroller is a __________ bit microcontroller 8 bit microcontroller 16 bit microcontroller 32 bit microcontroller None of the above None Hint 17). The microcontroller which will be dealing with 8 bit data that will be called as _________ 8 bit microcontroller 16 bit microcontroller 32 bit microcontroller None of the above None Hint 18). The microcontrollers are divided into how many categories? One Two Three Four None Hint 19). The 8051 microcontroller has______ 8 bit data bus 16 bit data bus 32 bit data bus None of the above None Hint 20). The 8051 microcontroller has______ 8 bit address bus 16 bit address bus 32 bit address bus None of the above None Hint Microcontrollers Quiz Questions and Answers 21). The ALU performs ______________ Arithmetic operations only Logical operations only Both a and b None of the above None Hint 22). The accumulator in an 8051 microcontroller is a ________ 8 bit register 16 bit register 32 bit register None of the above None Hint 23). What is the standard form of PSM? Program State Word Program Status Word Program Single Word None of the above None Hint 24). The stack pointer in 8051 architecture is a ________ 8 bit register 16 bit register 32 bit register None of the above None Hint 25). The data pointer in an 8051 architecture is a __________ 8 bit register 16 bit register 32 bit register None of the above None Hint 26). _____________is used as address pointer in order to access the instructions of the program Stack pointer Program Counter Data pointer None of the above None Hint 27). The microcontroller has only one or two instructions to move data between memory and CPU True False None Hint 28). How many bit handling instructions does microcontroller have? One Two Three None of the above None Hint 29). The access time for built in memory and input/output devices in microcontroller is ____ High Very high Less Better None Hint 30). The microcontroller requires less hardware devices True False None Hint 31). In microcontroller power consumption is _______ High Very high Less Better None Hint 32). The 8051 instructions divided into how many categories? Three Four Five Six None Hint 33). _________ instruction move the contents of a register to accumulator MOV instruction PUSH and POP XCHG instruction None of the above None Hint 34). ________ defines the byte type variable EQU (equate) DB (define byte) ASCII None of the above None Hint 35). When define byte assembly directive used to define data the numbers can be in _______ Decimal format Binary format Hex or ASCII format All of the above None Hint 36). The assembler always converts number (byte) to _______ format Decimal format Binary format Hexa decimal format All of the above None Hint 37). Which assembler directive is used to set the beginning address of the program? ORG (orginate) EQU (equate) DB (define byte) All of the above None Hint 38). How many bit handling instructions does microprocessor have? One Two One or two None of the above None Hint 39). The MOV instruction, push pop instruction, XCHG instruction comes under ___________ Arithematic instruction Data transfer instruction Bit manipulation instruction Branch instruction None Hint 40). In __________ the characters are placed in quotation marks Add description here! Decimal format Binary format ASCII format None of the above None Hint Microcontrollers Important Questions and Answers 41). The assembler directive _______ is placed at the end of the source and it acts as the last statement of the program ORG (orginate) EQU (equate) DB (define byte) END None Hint 42). ________ declare 24 byte stack in data segment that starts at internal RAM location 08H DS (Data Segment) DB (Define Byte) ORG (orginate) None of the above None Hint 43). __________ assembler directive declares the variables defined in a specific file that ca be used in the other source file Public assembler directive Data segment assembler directive Extern assembler directive END assembler directive None Hint 44). ____________ assembler directive declares the variables that are used in the present file but are defined in some other source file Public assembler directive Data segment assembler directive Extern assembler directive END assembler directive None Hint 45). The interrupt service routine always ends with return (RET) instruction, and the execution of the RET instruction results in ____________ POP the current stack top to PC POP the current stack top to PCW Both a and b None of the above None Hint 46). The interrupts in 8051 microcontroller are classified into __________ Two types Three types Four types Five types None Hint 47). How many external interrupts does 8051 microcontroller have? Two Three Four Five None Hint 48). If any internal peripheral generating an interrupt request that will be called an _________ External interrupt Internal interrupt Vectored interrupt None of the above None Hint 49). If any external peripheral generating an external request that will be called an _________ External interrupt Internal interrupt Vectored interrupt None of the above None Hint 50). The interrupts which can be disabled by the microcontroller using some instructions is called as _________ External interrupt Internal interrupt Vectored interrupt Non maskable interrupts None Hint 51). If the address provided by some peripheral devices that type of interrupts are called as __________ External interrupt Internal interrupt Non vectored interrupt Non maskable interrupts None Hint 52). In ___________ interrupts the starting address is fixed External interrupt Vectored interrupts Non vectored interrupt Non maskable interrupts None Hint 53). How many interrupts are available in 8051 microcontroller? Two Three Four Five None Hint 54). The 8051 microcontroller has five interrupts and the five interrupts are _________ External interrupt Maskable interrupt Vectored interrupts Both b and c None Hint 55). What are the five interrupts of 8051 microcontroller? External interrupt 0, external interrupt 1 Internal interrupt 0, internal interrupt 1 Timer 0 interrupt, timer 1 interrupt All of the above None Hint 56). __________ interrupts are the internal interrupts in 8051 microcontroller External interrupt 0, external interrupt 1 Serial interrupt Timer 0 interrupt, timer 1 interrupt Both b and c None Hint 57). The interrupt enable and interrupt priority registers in 8051 microcontroller is a ______ 8 bit register 16 bit register 32 bit register None of the above None Hint 58). How many oscillator periods defines the machine cycle 2 oscillator periods 4 oscillator periods 6 oscillator periods 12 oscillator periods None Hint 59). How many states does machine cycle consists of ______ Two states Four states Six states Twelve states None Hint 60). In reduced instruction set computer architecture the number of instructions involved is _______ High Less Better Very high None Hint Microcontrollers Interview Questions and Answers 61). In complex instruction set computer architecture the number of instructions involved is _______ More Less Better Very less None Hint 62). The small computer instructions provide _______ to the processors High speed Low speed Very low speed Very high speed None Hint 63). The applications of ARM processor are ______ Smart phones Multimedia players Tabs All of the above None Hint Read more about ARM Processor 64). The ARM processors are _______ Smaller in size Consumes less power Reduced complexity All of the above None Hint 65). The serial data communication in 8051 microcontroller uses ________ a) Synchronous method Asynchronous method Both synchronous and asynchronous method None of the above None Hint 66). What is the standard form of UART? Universal Asynchronous Synchronous Receiver Transmitter Universal Synchronous Receiver Transmitter Universal Asynchronous Receiver Transmitter None of the above None Hint Read more about UART 67). What is the standard form of USART? Universal Asynchronous Synchronous Receiver Transmitter Universal Synchronous Receiver Transmitter Universal Asynchronous Receiver Transmitter Universal Synchronous Asynchronous Receiver Transmitter None Hint 68). In which duplex the data is transmitted in one way at a time? Full-duplex Half-duplex Simplex None of the above None Hint 69). In which duplex the data is transmitted in both ways at the same time? Full-duplex Half-duplex Simplex None of the above None Hint 70). The serial control register (SCON register) operates in how many modes? One mode Two modes Three modes Four modes None Hint 71). The vector address of the timer interrupt 1 is ________ 000B 0003 001B None of the above None Hint 72). The mode 1 in the serial control register (SCON) is a ______ 8 bit UART with timer data rate 9 bit UART with set data rate 9 bit UART with timer data rate Synchronous serial communication None Hint 73). The mode 2 in the serial control register (SCON) is a ______ with set data rate 8 bit UART 9 bit UART 9 bit USART Synchronous serial communication None Hint 74). The mode 3 in the serial control register (SCON) is a ______ 8 bit UART with timer data rate 9 bit UART with set data rate 9 bit UART with timer data rate Synchronous serial communication None Hint 75). What is the standard of the SBUF register? Serial buffer register Parallel buffer register Standard buffer register None of the above None Hint 76). The serial buffer register is an ______ 8 bit register 16 bit register 32 bit register None of the above None Hint 77). How many transistors do small scale integration IC’s require? <10 transistors 10-100 transistors 100-10k transistors 10k transistors None Hint 78). How many transistors do medium scale integration IC’s require? <10 transistors 10-100 transistors 100-10k transistors 10k transistors None Hint 79). How many transistors do large-scale integration IC’s require? <10 transistors 10-100 transistors 100-10k transistors 10k transistors None Hint 80). How many transistors do very large-scale integration IC’s require? <10 transistors 10-100 transistors 100-10k transistors 10k transistors None Hint Microcontrollers Questions and Answers for Engineers 81). Which one is the bit addressable register? SBUF PCON SCON TMOD None Hint 82). Which of the following is an 8 bit register? Program status word, Timer control register Accumulator Both a and b None of the above None Hint 83). Which register provides the status and control information about the serial port is _________ Only SCON Only PCON TSCON PCON & SCON None Hint 84). Which register provides control and status information about counters is ________ Only SCON TMOD Only TSCON PCON and SCON None Hint 85). The receive buffer of the serial data buffer is a_______ Serial in parallel out register Serial in serial out register Parallel in parallel out register Parallel in serial out register None Hint 86). Which register contains the status information? Control registers Instruction registers Program status word PCON and SCON None Hint 87). Which register used as a scratchpad? B registers Instruction registers Program status word Status registers None Hint 88). Which register used as an operand register? Accumulator Instruction registers Program status word Accumulator and B register None Hint 89). Which register is used for accessing the external data memory? LDPTR DPTRL DPTR None of the above None Hint 90). The vector address of the external interrupt 0 is ________ 000B 0003 001B None of the above None Hint 91). The vector address of the external interrupt 1 is ________ 000B 0003 0013 None of the above None Hint Time's up