Microprocessor
A sequence of two registers that multiplies the content of DE register pair by two and stores the result in HL register pair (in 8085 assembly language) is

 PCHL & DAD D
 XTHL & DAD H
 XCHG & DAD B
 XCHG & DAD H

ANSWER DOWNLOAD EXAMIANS APP

Microprocessor
HLDA signal in 8085 performs the following operation:

 Hold the data in the accumulator until the microprocessor is turned OFF.
 Indicates that the CPU has received the HOLD request and that it will relinquish the bus in the next clock cycle.
 Indicates that the CPU has not received the HOLD request.
 Indicates that another master is requesting the use of the address and data buses.

ANSWER DOWNLOAD EXAMIANS APP

Microprocessor
Assertion(A): Monostablemultivibrators (IC74121) are used in a microprocessor based system for frequency measurement. Reason(R): Microprocessor counts the number of interrupt signals/second or within a specified interval through ISR.

 Both A & R are true but R is not the correct explanation of A.
 A is true but R is false.
 A is false but R is true.
 Both A & R are true and R is the correct explanation of A.

ANSWER DOWNLOAD EXAMIANS APP