Digital Electronics-Computers
Digital Electronics-Computers
11. What is occurring when two or more sources of data attempt to use the same bus?
- Bus contention
- Direct memory access
- Bus interruption
- PPI
12. Which of the following is not a jump instruction?
- JB (jump back)
- JA (jump above)
- JO (jump if overflow)
- JMP (unconditional jump)
13. Which of the following was not a design improvement for the 8086/8088 over the 8085?
- Execution unit (EU)
- 16-bit data bus
- Arithmetic logic unit (ALU)
- Bus interface unit (BIU)
14. Polled I/O works best when ________.
- there are no priority considerations
- priority considerations are frequent
- the polling rate exceeds 1000 s
- the polling rate is below 1000 s
15. Which of the following is not an arithmetic instruction?
- INC (increment)
- CMP (compare)
- DEC (decrement)
- ROL (rotate left)
16. During a read operation the CPU fetches ________.
- a program instruction
- another address
- data itself
- all of the above
17. The first Intel microprocessor to contain on-board cache memory was the ________.
- 80386
- 80486
- Pentium
- Pentium Pro
18. Which of the following is not an 8086/8088 general-purpose register?
- Code segment (CS)
- Data segment (DS)
- Stack segment (SS)
- Address segment (AS)
19. Which of the following is not a computer bus?
- Data bus
- Control bus
- Timer bus
- Address bus
20. With interrupt-driven I/O, if two or more devices request service at the same time, ________.
- the device closest to the CPU gets priority
- the device that is fastest gets priority
- the device assigned the highest priority is serviced first
- the system is likely to crash