WorksheetsMCQ6 for 8051
Total questions: 25
Worksheet time: 13mins
Which of the following comes under the indexed addressing mode?
MOVX A, @DPTR
MOVC A, @A+DPTR
MOV A,R0
MOV @R0,A
When the microcontroller executes some arithmetic operations, then the flag bits of which register are affected?
PSW
SP
DPTR
PC
8051 microcontroller has how many 16 bit registers?
2
3
1
0
How are the bits of the register PSW affected if we select Bank2 of 8051?
PSW.5=0 and PSW.4=1
PSW.2=0 and PSW.3=1
PSW.3=1 and PSW.4=1
PSW.3=0 and PSW.4=1
On power up, the 8051 uses which RAM locations for register R0- R7?
00-2F
00-07
00-7F
00-0F
How many bytes of bit addressable memory is present in 8051 based microcontrollers?
8 bytes
32 bytes
16 bytes
128 bytes
While programming the ADC0808/0809 IC what steps are followed?
select the analog channel, start the conversion, monitor the conversion, display the digital results
select the analog channel, activate the ALE signal (H to L pulse), start the conversion, monitor the conversion, read the digital results
select the analog channel, activate the ALE signal (H to L pulse), start the conversion, read the digital results
select the channel, start the conversion, end the conversion
8 input DAC has ________
8 discrete voltage levels
64 discrete voltage levels
128 discrete voltage levels
256 discrete voltage levels
The 8255 is a ______ chip.
Input/Output
Analog to Digital
Digital to analog
None of the mentioned
How many pins of the 8255 can be used as the I/O ports?
8
16
24
32
How many data lines are there in a 16*2 alphanumeric LCD IC?
16
8
1
0
Which pin of the LCD is used for adjusting its contrast?
1
2
3
4
For writing commands on an LCD, RS bit is
set
reset
set & reset
none of the mentioned
Which command of an LCD is used to on the display and cursor character not blinking?
0x0E
0x18
0x05
0x07
Which of the following step/s is/are correct for sending data to an LCD?
reset the R/W bit
High to low pulse to the E bit
set the RS bit
all of the mentioned
The RS pin is _________ for an LCD.
input
output
input & output
none of the mentioned
Which pin of the external hardware is said to exhibit INT0 interrupt?
10
11
12
13
Which devices are specifically being used for converting serial to parallel and from parallel to serial respectively?
timers
counters
registers
serial communication
When we add two numbers the destination address must always be.
some immediate data
any register
accumulator
memory
If SUBB A,R4 is executed, then actually what operation is being applied?
R4+A
R4-A
A-R4
R4+A
ANL instruction is used _______
to AND the contents of the two registers
to mask the status of the bits
all of the mentioned
none of the mentioned
XRL, ORL, ANL instructions have _______
accumulator as the destination address and any register, memory or any immediate data as the source address
accumulator as the destination address and any immediate data as the source address
any register as the destination address and accumulator, memory or any immediate data as the source address
any register as the destination address and any immediate data as the source address
To initialize any port as an output port what value is to be given to it?
0XFF
0X00
0X01
A port is by default an output port
Which of the ports act as the 16 bit address lines for transferring data through it?
PORT 0 and PORT 1
PORT 1 and PORT 2
PORT 0 and PORT 2
PORT 1 and PORT 3
Which instruction is used to check the status of a single bit?
MOV A,P0
ADD A,#05H
JNB PO.0, label
CLR P0.5
