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8085 microprocessor questions

1. What are the various registers in 8085? - Accumulator register, Temporary register, Instructionregister, Stack Pointer, Program Counter are the various registers in 808 .

!. In 8085 name the 16 bit registers? - Stack pointer an" Program counter all have 1# $its.%. What are the various flags used in 8085? - Sign &lag, 'ero &lag, Au(illary &lag, Parity &lag, Carry &lag.). What is Stack ointer? - Stack pointer is a special purpose 1#-$it register in the *icroprocessor, +hich

hol"s the a""ress o& the top o& the stack.. What is rogram counter? - Program counter hol"s the a""ress o& either the &irst $yte o& the ne(t

instruction to $e &etche" &or e(ecution or the a""ress o& the ne(t $yte o& a multi $yte instruction, +hich hasnot $een completely &etche". In $oth the cases it gets incremente" automatically one $y one as theinstruction $ytes get &etche". Also Program register keeps the a""ress o& the ne(t instruction.

#. Which Stack is used in 8085? - I / ast In irst ut stack is use" in 808 .In this type o& Stack thelast store" in&ormation can $e retrieve" &irst.

. What happens !hen "#$ instruction is e%ecuted in processor? - The *icro Processor enters into2alt-State an" the $uses are tri-state".

8. What is meant b& a bus? - A $us is a group o& con"ucting lines that carriers "ata, a""ress, 3 controlsignals.

4. What is $ri'state logic? - Three ogic evels are use" an" they are 2igh, o+, 2igh impe"ance state. Thehigh an" lo+ are normal logic levels 3 high impe"ance state is electrical open circuit con"itions. Tri-statelogic has a thir" line calle" ena$le line.

10. (ive an e%ample of one address microprocessor? - 808 is a one a""ress microprocessor.11. In !hat !a& interrupts are classified in 8085? - In 808 the interrupts are classi&ie" as 2ar"+are

an" So&t+are interrupts.1!. What are "ard!are interrupts? - T5AP, 5ST . , 5ST#. , 5ST . , I6T5.1%. What are Soft!are interrupts? - 5ST0, 5ST1, 5ST!, 5ST%, 5ST), 5ST , 5ST#, 5ST .1). Which interrupt has the highest priorit&? - T5AP has the highest priority.

1 . )ame 5 different addressing modes? - Imme"iate, 7irect, 5egister, 5egister in"irect, Implie"a""ressing mo"es.

1#. "o! man& interrupts are there in 8085? - There are 1! interrupts in 808 .1 . What is clock frequenc& for 8085? - % *2 is the ma(imum clock &re9uency &or 808 .18. What is the *S$ for the $*+ ? - 5ST ). is calle" as T5AP.14. In 8085 !hich is called as "igh order , #o! order *egister? - lag is calle" as o+ or"er register 3

Accumulator is calle" as 2igh or"er 5egister.!0. What are input - output devices? - :ey$oar"s, loppy "isk are the e(amples o& input "evices. Printer,

;7 < C7 "isplay, C5T *onitor are the e(amples o& output "evices.!1. .an an *. circuit be used as clock source for 8085? - =es, it can $e use", i& an accurate clock

&re9uency is not re9uire". Also, the component cost is lo+ compare" to C or Crystal.

!!. Wh& cr&stal is a preferred clock source? - >ecause o& high sta$ility, large ? /?uality actor 3 the&re9uency that "oesn@t "ri&t +ith aging. Crystal is use" as a clock source most o& the times.!%. Which interrupt is not level'sensitive in 8085? - 5ST . is a raising e"ge-triggering interrupt.!). What does /ualit& factor mean? - The ?uality &actor is also "e&ine", as ?. So it is a num$er, +hich

re&lects the lossness o& a circuit. 2igher the ?, the lo+er are the losses.! . What are level'triggering interrupt? - 5ST #. 3 5ST . are level-triggering interrupts.

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8086 intervie! questions>y admin Banuary 4, !00

1. What are the flags in 8086? - In 808# Carry &lag, Parity &lag, Au(iliary carry &lag, 'ero &lag, ver&lo+&lag, Trace &lag, Interrupt &lag, 7irection &lag, an" Sign &lag.

!. What are the various interrupts in 8086? - *aska$le interrupts, 6on-*aska$le interrupts.

%. What is meant b& askable interrupts? - An interrupt that can $e turne" o&& $y the programmer iskno+n as *aska$le interrupt.

). What is )on' askable interrupts? - An interrupt +hich can $e never $e turne" o&& /ie."isa$le" iskno+n as 6on-*aska$le interrupt.

. Which interrupts are generall& used for critical events? - 6on-*aska$le interrupts are use" incritical events. Such as Po+er &ailure, ;mergency, Shut o&& etc.,

#. (ive e%amples for askable interrupts? - 5ST . , 5ST#. , 5ST . are *aska$le interrupts. (ive e%ample for )on' askable interrupts? - Trap is kno+n as 6on-*aska$le interrupts, +hich is

use" in emergency con"ition.8. What is the a%imum clock frequenc& in 8086? - *h is the *a(imum clock &re9uency in 808#.4. What are the various segment registers in 8086? - Co"e, 7ata, Stack, ;(tra Segment registers in

808#.10. Which Stack is used in 8086? - I / irst In irst ut stack is use" in 808#.In this type o& Stack the

&irst store" in&ormation is retrieve" &irst.11. What are the address lines for the soft!are interrupts?

RST 0 0000 H

RST1 0008 H

RST2 0010 H

RST3 0018 H

RST4 0020 H

RST5 0028 H

RST6 0030 H

RST7 0038 H

1!. What is SI and *I instructions? - SI* is Set Interrupt *ask. se" to mask the har"+are interrupts.5I* is 5ea" Interrupt *ask. se" to check +hether the interrupt is *aske" or not.1%. Which is the tool used to connect the user and the computer? - Interpreter is the tool use" to

connect the user an" the tool.1). What is the position of the Stack ointer after the S" instruction? - The a""ress line is 0! less

than the earlier value.1 . What is the position of the Stack ointer after the 2 instruction? - The a""ress line is 0!

greater than the earlier value.1#. #ogic calculations are done in !hich t&pe of registers? - Accumulator is the register in +hich

Arithmetic an" ogic calculations are "one.1 . What are the different functional units in 8086? - >us Inter&ace nit an" ;(ecution unit, are the t+o

"i&&erent &unctional units in 808#.18. (ive e%amples for icro controller? - '80, Intel *SC 1 34#, *otorola are the $est e(amples o&

*icrocontroller.14. What is meant b& cross'compiler? - A program runs on one machine an" e(ecutes on another is calle"

as cross-compiler.!0. What are the address lines for the hard!are interrupts? -