CS609-System Programming Quiz MCQS #Objective #Questions #MidTerm
1. Bit no. ___ of EFLAG is used for alignment check
- 12
- 14
- 15
- 18 ✔
2. In ___ each byte is needed to be encapsulated in start and end
- Synchronous Communication
- Asynchronous Communication ✔
- Both a and b
- Serial and Hybrid Communication
3. Base address of LPT1 port in BIOS Data Area is ___
- 08:40
- 40:08 ✔
- 40:90
- 60:40
4. An I/O device cannot be directly connected to the buses so they generally require a ___ to be placed between the CPU and I/O device
- Controller ✔
- Pipeline
- Data Bus
- I/O Bus
5. To set the Interrupt Vector Table (IVT) means that to change the ___ sized interrupt vector within the IVT
- Quad Word
- Double Word ✔
- Byte
- Nibble
6. DB25 connector is used to connect ___
- Address Bus
- PPI ✔
- Mobile
- CPU
7. In self test mode the output of UART is routed to its input
- True ✔
- False
8. Bit number ___ of port 64H Status register used for input buffer full
- 0
- 1 ✔
- 2
- 3
9. The device which requires timing signal is called ___
- Synchronous ✔
- Asynchronous
- Active
- Un-Active
10. The ___ register of Real Time Clock is used to enable interrupt on various events like alarm time and time-up duration
- Status Register C
- Status Register A
- Status Register D
- Status Register B ✔
11. DTE is ___
- Data Terminal Equipment ✔
- Data Transmitting Equipment
- Dual Terminal Equipment
- Data Termination Equivalence
12. First two bytes of any Far address contains ___ address
- Segment
- Offset ✔
- Both Segment and Offset
- NULL
13. In the context of Keyboard Interface, ___ means Typematic rate will be sent in next byte
- 0xFF
- 0xF3 ✔
- 0xED
- 0xE5
14. A software interrupt does not require ___
- Memory
- An Entry in IVT
- EOI(End of Interrupt) ✔
- Interrupt number
15. Keyboard buffer is ___ bytes in size
- 8
- 16
- 32 ✔
- 64
16. The address of partition block on hard disk is ___
- head # = 1, track# = 0 and sector # = 1 ✔
- head # = 0, track# = 0 and sector # = 0
- head # = 1, track# = 1 and sector # = 1
- head # = 0, track# = 0 and sector # = 1
17. There are ___ main types of serial communication
- 2 ✔
- 3
- 4
- 5
18. A code 0xFA on the port 60H (Keyboard Interface) indicates that the byte has been received ___
- Properly ✔
- With Errors
- With acknowledgement
- Duplicate values
19. Bit number ___ of port 64H Keyboard Status Register indicate status of Time-Out error during output
- 4
- 5
- 6 ✔
- 7
20. Clock status register ___ is main control register
- A
- B ✔
- C
- D
21. There are differences in mechanism of invocation of interrupt and event driven procedures
- Yes ✔
- No
22. A compiled TSR program has ___ extension
- .Doc
- .COM
- .XLS
- .C ✔
23. ___ interrupt is used to read time from Real Time Clock
- 1A/02H ✔
- 1A/03H
- 1A/04H
- 1A/05H
24. If UART is running in Self-Test Mode, then all the input from the UART is directed to the ___
- Keyboard
- Upper part of the screen
- Lower part of the screen ✔
- Printer
25. We have set the bit No. 7 of IMR (Interrupt Mask Register) to unmask the Interrupt so that interrupt ___ can occur at ___ line
- 0xf, IRQ 7 ✔
- 0xa, IRQ 6
- 0x8, IRQ 5
- 0x6, IRQ 2
26. keep() function has ___ parameters while exit() function has ___ parameters
- 0, 2
- 1, 2
- 2, 0
- 2, 1 ✔
27. In Keyboard Status Byte, bit no. 2 and 3 are used for CTRL and ALT keys respectively. Which of the following condition is used to check that CTRL + ALT keys are pressed Where:
unsigned char far * scr = (unsigned char far *)(0x00400017)
- if(((*scr) & 12) == 12) ✔
- if(((*scr) & 8) == 8)
- if(((*scr) & 4) == 4)
- if(((*scr) & 2) == 2)
28. The BIOS data area in memory starts at the address of ___
- 0020:0000
- 0030:0000
- 0040:0000 ✔
- 0050:0000
29. Select the correct option that does NOT belong to the uses of I/O Controller
- Listen sound tracks from PC headphones
- Sending document to printer for printing
- Sending graphics to VGA card for displaying on the monitor
- Applying security options on storage media ✔
30. The amount of memory above conventional memory can be determined using the service
- 15H/88H ✔
- 13H/88H
- 11H/88H
- 17H/88H
31. DMA stands for ___
- Direct Memory Access ✔
32. Standard PC operates in two modes in terms of memory which are
- Real mode and protected mode ✔
33. UART stands for ___
- Universal Asynchronous Receiver Transmitter ✔
34. Usually interrupt procedures are reentrant procedures especially those interrupt procedure compiled using C language compiler are reentrant
- True ✔
35. Interrupt Vector Table (IVT) in short is a ___ bytes sized table
- 1024 ✔
36. Hardware Interrupts are ___
- Preemptive
- Non-Preemptive ✔
37. Timer interrupt is a ___
- Hardware Interrupt ✔
- Software Interrupt
38. Int 14H ___ can be used to set the line parameter of the UART or COM port
- Service # 0 ✔
39. The keyboard makes use of interrupt number ___ for its input operations
- 9 ✔
- 10
- 11
- 12
40. In case of synchronous communication a timing signal is required to identify the start and end of a bit
- True ✔
- False
41. Register can be used to divide frequency is ___
- Counter Register ✔
- Accumulator Register
42. Only ___ ports are important from programming point of view
- 70 and 71H ✔
43. Which port is known as Data Port ___
- 60H ✔
- 61H
- 64H
- 69H
44. LPTs can be swapped
- True ✔
- False
45. PPI is used to perform parallel communication
- True ✔
- False
46. ___ is used to control the printer via the BIOS
- Int 16H
- Int 17H ✔
47. ___ bit is cleared to indicate the low nibble is being sent
- D1
- D2
- D4 ✔
48. DSR stands for ___
- Data set ready ✔
49. There are two main types of interrupts namely ___
- Hardware interrupts and Software interrupts ✔
50. To set the interrupt vector means to change the double word sized interrupt vector within IVT
- True ✔
- False
51. The service number is usually placed in the ___ register
- AL
- CL
- AH ✔
- AX
52. The service ___ is called the keyboard hook service
- 15H/2FH
- 15H/4FH ✔
- 15H/FFH
53. The BIOS interrupt ___ can be used to configure RTC
- 1AH ✔
- 2AH
54. The interval timer can operate in ___ modes
- Five
- Seven
- Six ✔
55. ___ is Disk interrupt
- 10H
- 13H ✔
56. PPI stands for
- Peripheral Programmable interface ✔
57. Int ___ is used to control the printer via the BIOS
- 17H ✔
- 18H
- 20 H
58. Counter register can be used to divide clock signal
- True ✔
- False
59. DCE stands for ___
- Data communication equipment ✔
60. ___ is used to identify the cause of interrupt
- Interrupt ID Register
- PC Register
61. The bit number ___ of the coprocessor control word is the interrupt enable flag
- 7 ✔
- 8
62. The output on the monitor is controlled by a controller called ___
- Video controller ✔
- Bus controller
63. The keyboard input character scan code is received at ___ port
- 60H ✔
- 62H
64. ___ is LED control byte
- 0xFD
- 0xED ✔
- 0xFF
65. BPB stands for ___
- BIOS parameter block ✔
66. The function of I/O controller is to provide ___
- I/O control signals
- Buffering
- Error Correction and Detection
- All of the given ✔
67. IVT is a table containing ___ byte entries each of which is a far address of an interrupt service routine
- 2
- 4 ✔
- 8
68. Each paragraph in keep function is ___ bytes in size
- 4
- 8
- 16 ✔
69. Interrupt 9 usually reads the ___ from keyboard
- ASCII code
- Scan code ✔
