1. The 8085 microprocessor responds to the presence of an interrupt ___________
a) As soon as the trap pin becomes ‘LOW’
b) By checking the trap pin for ‘high’ status at the end of each instruction fetch
c) By checking the trap pin for ‘high’ status at the end of execution of each instruction
d) By checking the trap pin for ‘high’ status at regular intervals
Explanation: The 8085 microprocessor are designed to complete the execution of the current instruction and then to service the interrupts.
2. CPU as two modes privileged and non-privileged. In order to change the mode from privileged to non-privileged
a) A hardware interrupt is needed
b) A software interrupt is needed
c) Either hardware or software interrupt is needed
d) A non-privileged instruction (which does not generate an interrupt)is needed
Explanation: A software interrupt by some program which needs some CPU service, at that time the two modes can be interchanged.
3. Which interrupt is unmaskable?
a) RST 5.5
b) RST 7.5
c) TRAP
d) Both RST 5.5 and 7.5
Explanation: The trap is a non-maskable interrupt as it deals with the ongoing process in the processor. The trap is initiated by the process being executed due to lack of data required for its completion. Hence trap is unmaskable.
4. From amongst the following given scenarios determine the right one to justify interrupt mode of data transfer.
i) Bulk transfer of several kilo-byte
ii) Moderately large data transfer of more than 1kb
iii) Short events like mouse action
iv) Keyboard inputs
a) i and ii
b) ii
c) i, ii and iv
d) iv
Explanation: iv
5. How can the processor ignore other interrupts when it is servicing one ___________
a) By turning off the interrupt request line
b) By disabling the devices from sending the interrupts
c) BY using edge-triggered request lines
d) All of the mentioned
Explanation: All of the mentioned
6. If during the execution of an instruction an exception is raised then __________
a) The instruction is executed and the exception is handled
b) The instruction is halted and the exception is handled
c) The processor completes the execution and saves the data and then handle the exception
d) None of the mentioned
Explanation: Since the interrupt was raised during the execution of the instruction, the instruction cannot be executed and the exception is served immediately.
7. _____ is/are types of exceptions.
a) Trap
b) Interrupt
c) System calls
d) All of the mentioned
Explanation: All of the mentioned
8. The program used to find out errors is called __________
a) Debugger
b) Compiler
c) Assembler
d) Scanner
Explanation: Debugger is a program used to detect and correct errors in the program
9. The two facilities provided by the debugger is __________
a) Trace points
b) Break points
c) Compile
d) Both Trace and Break points
Explanation: The debugger provides us with the two facilities to improve the checking of errors.
10. In trace mode of operation is ________
a) The program is interrupted after each detection
b) The program will not be stopped and the errors are sorted out after the complete program is scanned
c) There is no effect on the program, i.e the program is executed without rectification of errors
d) The program is halted only at specific points
Explanation: In trace mode, the program is checked line by line and if errors are detected then exceptions are raised right away.