IBM 5150 Hardware Reference Manual page 363

40. Hertz (Hz.): A unit offrequency equal to one cycle per second.
41. High order position: The leftmost position in a string of
characters.
42. Input/Output (I/O): Pertaining to a device or to a channel that
may be involved in an input process, and, at a different time, in
an output process. (2) Pertaining to a device whose parts can be
performing an input process and an output process at the same
time.
43. Integrated Circuit: A combination of interconnected circuit
elements inseperably associated on or within a continuous
substrate.
44. Interpreter: A computer program used to interpret. Synony ­
mous with interpretive program.
45. Interrupt: (1) A suspension of a process, such as the execution
of a computer program, in such a way that the process can be
resumed. (2) To stop a process in such a way that it can be
resumed. (3) In data transrnission, to take an action at a
receiving station that causes the transmitting station to termin ­
ate a transmission.
46. I/O Channel: Input/Output Channel. In a data processing
system, a functional unit, controlled by the processing unit, that
handles the transfer of data between main storage and peri ­
pheral equipment.
47. I/OCH CK: I/O Channel Check. (Refer to System Board I/O
Channel Descriptions).
48. I/O CH ROY: I/O Channel Ready. (Refer to System Board
I/O Channel Descriptions).
49. IMR: Interruption Mask Register.
50. lOR: I/O Read Command. (Refer to System Board I/O
Channel Descriptions).
51. lOW: I/O Write Command: (Refer to System Board I/O
Channel Descriptions).
52. IRQ2-IRQ7: Interrupt Request 2 to 7. (Refer to System Board
I/O Channel Descriptions).
53. K: An abbreviation for the prefix kilo, i.e. 1000 in decimal
notation. To the tenth power, 1024 in decimal notation.
54. KB: Kilobyte.
55. Khz: Kilohertz. A unit of frequency equal to 1,000 hertz.
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