GATE EE 2009 | Microprocessor Question 7 | Digital Electronics

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GATE EE 2009

MCQ (Single Correct Answer)

-0.6

In $$8085$$ microprocessor, the contents of the Accumulator, after the following instructions are executed will become

$$\eqalign{ & XRA\,\,\,A \cr & MVI\,\,\,B\,\,\,F0\,\,\,H \cr & SUB\,\,\,B \cr} $$

$$01$$ $$H$$

$$0F$$ $$H$$

$$F0$$ $$H$$

$$10$$ $$H$$

GATE EE 2008

MCQ (Single Correct Answer)

-0.6

The contents (in Hexadecimal) of some of the memory locations in an $$8085A$$ based system are given below GATE EE 2008 Digital Electronics - Microprocessor Question 9 English

GATE EE 2008 Digital Electronics - Microprocessor Question 9 English

The contents of stack pointer $$(SP),$$ program counter $$(PC)$$ and $$(HL)$$ are $$270H,$$ $$2100H$$ and $$0000H$$ respectively. When the following sequence of instructions are executed,
$$2100H:$$ $$DAD$$ $$SP$$
$$2101H;$$ $$PCHL$$

The contents of $$(SP)$$ and $$(PC)$$ at the end of execution will be

$$\left( {PC} \right) = 2102H,\,\,\left( {SP} \right) = 2700H$$

$$\left( {PC} \right) = 2700H,\,\,\left( {SP} \right) = 2700H$$

$$\left( {PC} \right) = 2800H,\,\,\left( {SP} \right) = 26FEH$$

$$\left( {PC} \right) =2A02H,\,\,\left( {SP} \right) = 2702H$$

GATE EE 2007

MCQ (Single Correct Answer)

-0.6

In an $$8085$$ $$A$$ microprocessor based system, it is desired to increment the contents of memory location whose address is available in $$(D,E)$$ register pair and store the result in same location. The sequence of instructions is

$$XCHG,\,\,INR\,\,\,M$$

$$XCHG,\,\,INX\,\,\,H$$

$$INX\,\,D,\,\,XCHG$$

$$INR\,\,M,\,\,XCHG$$

GATE EE 2007

MCQ (Single Correct Answer)

-0.6

Which one of the following statements regarding the $$INT$$ (interrupt) and the $$BRQ$$ (bus request) pins in a $$CPU$$ is true?

The $$BRQ$$ pin is sampled after every instruction cycle, but the $$INT$$ is sampled after every machine cycle

Both $$INT$$ and $$BRQ$$ are sampled after every machine cycle

The $$INT$$ pin is sampled after every instruction cycle, but the $$BRQ$$ is sampled after every machine cycle

Both $$INT$$ and $$BRQ$$ are sampled after every instruction cycle