Computer Architecture
Covers digital logic circuits (adders, subtractors, logic gates, multiplexers, encoders) and 8085 microprocessor instructions for data movement and arithmetic operations.
Questions
Which logic circuit requires one Ex-OR gate for sum generation and one AND gate for carry generation?
- Full adder
- Half adder
- Full subtrator
- NAND logic
- NOR logic
Which of the following provides a means of loading any register pair with a two byte value in 8085 processor?
- MVI Group
- LDA and STA
- LXI instruction
- Instruction
- ADD instructions
Which circuit requires one Ex-OR gate for difference generation and one AND gate with a NOT gate for borrow generation?
- Half subtractor
- Full subtractor
- Full adder
- Not logic
- NAND logic
Which of the following instructions are the general means of moving data between memory and registers in 8085 processor?
- LDA and STA
- MVI group
- MOV group
- ADD instructions
- Stack pointer
Which of the following instructions provides a means of moving data between the accumulator and a memory location indirectly, with the RAM address contained in either BC or DE register pair in 8085 processor?
- LDA and STA
- MVI group
- ADD instructions
- LDAX and STAX
- Subtract instructions
Which of the following logic gates has low output only when all the inputs are high at the same time?
- AND gate
- OR gate
- Ex-Nor gate
- NAND gate
- Step recovery
Which logic circuitry is required to detect whenever the sum is greater than 01001, so that the correction can be added in?
- BCD adders
- Full subtractor
- Full adder
- Ex-OR logic
- NOT logic
Which of the following is/are used to provide means of adding a fixed value into the accumulator in 8085 processor?
- MVI group
- Subtract instructions
- ADD instructions
- Control unit
- ADD immediates
In which logic gate is the output high only when both the inputs are low?
- Ex-Nor gate
- AND gate
- OR gate
- Step recovery
- NOR gate
Which instruction allows the programmer to match the byte in the accumulator with a fixed mask byte, contained in the second byte of the instructions in 8085 processor?
- Compare immediate
- AND instructions
- AND immediate
- ADD instructions
- MVI group
Which of the following provides a means of subtracting a fixed value from the contents of the accumulator in 8085 processor?
- Subtract instructions
- Subtract immediate
- ADD instructions
- LDA and STA
- Instruction
Which of the following provides a means of moving two bytes between the HL register pair and a RAM address in 8085 processor?
- LDA and STA
- LHLD and SHLD
- MVI group
- ADD instructions
- Operand
Which of the following is a device that allows digital information from several sources to be routed onto a single output line for transmission over to a common destination?
- Multiplexer
- Demultiplexer
- Decoder
- Full subtractor
- Conversion rate
Which of the following allows an address to be built in the DE pair and then ready to be transferred at once to the HL pair in 8085 processor?
- MVI group
- LDA and STA
- ADD instructions
- Subtract instructions
- XCHG instruction
Which of the following accepts an active level on two or more of its inputs representing digits, such as decimal or octal and converts it to a coded output such as binary or BCD?
- Decoder
- Encoder
- BCD adder
- Full subtractor
- Full adder