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37. On all instruction cycles, the processor accesses memory at least once, to: .

38. When a processor attempts to read a byte or word of memory, it firstly checks the:

39. Block size is:

40. This determines which cache location the block will occupy:

41. This chooses which block to replace when a new block is to be loaded into the cache and the cache already had all slots filled with other blocks:

42. If the contents of a block in the cache are altered, then it is needed to save it back to main memory before replacing it. This is called:

43. Which of the following is not a technique possible for I/O operations?

44. The processor issues an I/O command to a module and waits, periodically checking the status of the I/O module until it finds that the operation is complete.

45. The I/O module performs the requested action and then sets the appropriate bits in the I/O status register but takes no further action to alert the processor.

47. The main disadvantage of this technique: it is a time-consuming process that keeps the processor busy needlessly.

48. The processor issues an I/O command to a module and then go on to some other useful work.

49. The I/O module performs the requested action and alerts the processor to request service when it is ready to exchange data with the processor.

51. The main disadvantage of this technique: consumes a lot of processor time, because every word of data that goes from memory to I/O module or from I/O module to memory must pass through the processor.

52. The processor issues an I/O command to a separate module, by sending the type of operation (четыре вопроса в одном)read/write), the address of the I/O device, the starting location in memory for data, number of words. Then the processor continues with other work.

53. The module transfers the entire block of data to/from memory without going through the processor.

55. The main disadvantage of this technique: there is a competition for bus usage.