Questions
41
What is the required baud rate for an efficient operation of serial port devices in 8051 microcontroller?
Answer: 9600
42
Which port does not represent quasi-bidirectional nature of I/O ports in accordance to the pin configuration of 8051 microcontroller?
Answer: Port 0 (Pins 32-39)
43
Where should the pin 19 (XTAL1), acting as an input of inverting amplifier as well as part of an oscillator circuit, be connected under the application of external clock?
Answer: to GND
44
Which mode of timer 2 allow to hold the reload values with an assistance of RCAP2H & RCAP2L register pair?
Answer: 16 bit auto reload mode
45
Which registers are supposed to get copied into RCAP2H & RCAP2L respectively due to the transition at 8052 T2EX pin in the capture mode operation?
Answer: TH2 & TH2
46
Which timer is attributed to the register pair of RCAP2H & RCAP2L for capture mode operation?
Answer: Timer 2
47
Which among the below stated registers does not belong to the category of special function registers?
Answer: SP & PC
48
What is the maximum capability of addressing the off-chip data memory & off-chip program memory in a data pointer?
Answer: 64K
49
Which instruction find its utility in loading the data pointer with 16 bits immediate data?
Answer: MOV
50
Which commands are used for addressing the off-chip data and associated codes respectively by data pointer?
Answer: MOVX & MOVC
51
Which locations of 128 bytes on-chip additional RAM are generally reserved for special functions?
Answer: 80H to 0FFH
52
It is possible to set the auxiliary carry flag while performing addition or subtraction operations only when the carry exceeds _______
Answer: 3rd bit
53
Which register bank is supposed to get selected if the values of register bank select bits RS1 & Rs0 are detected to be ‘1’ & ‘0’ respectively?
Answer: Bank 2
54
Which flags represent the least significant bit (LSB) and most significant bit (MSB) of Program Status Word (PSW) respectively?
Answer: Parity Flag & Carry Flag
55
Which bit/s play/s a significant role in the selection of a bank register of Program Status Word (PSW)?
Answer: Both a & b
56
What is the default value of stack once after the system undergoes the reset condition?
Answer: 07H
57
Which among the below mentioned functions does not belong to the category of alternate functions usually performed by Port 3 (Pins 10-17)?
Answer: Internal Interrupts
58
What is the constant activation rate of ALE that is optimized periodically in terms of an oscillator frequency?
Answer: 1 / 6
59
Which output control signal is activated after every six oscillator periods while fetching the external program memory and almost remains high during internal program execution?
Answer: PSEN
60
Which memory allow the execution of instructions till the address limit of 0FFFH especially when the External Access (EA) pin is held high?
Answer: Internal Program Memory
