7-41. Input and output chains deal primarily with which
of the following activities?
1. The processing of IOC control words
2. Specification of the locations of external status
words
3. Transfer of blocks of information
4. Addresses provided by the load control
memory command
7-42. Data transfer between the computer and external
equipments will take place when which of the
following conditions is/are met?
1. The memory areas for the data have been
specified by the computer programs
2. The external equipment is ready to send or
receive data and has sent a request signal
3. Initiate input/output or equivalent instruction
is executed by the CPU
4. All of the above
7-43. Which of the following is one of the constants in
all I/O operations?
1. Data words will always be limited to 16 bits
2. When the data transfer will begin
3. The circuitry required to connect external
equipments
4. A serial data interface between the computer
and external equipments
7-44. In I/O operations, communications with the
external equipment require which of the following
devices/operating modes?
1. An IOC
2. A single channel operating mode
3. Circuitry that specifies a sequence of events
4. A dual channel operating mode
7-45. When an index address in main memory is
specified by an external equipment during an I/O
operation, the computer is operating in which of
the following modes?
1. Intercomputer channel mode
2. Externally specified index mode
3. Externally specified address mode
4. Dual channel mode
7-46. In I/O operations, which of the following is one of
the primary uses of registers?
1. To enable and route data information only
2. To enable and route control information only
3. To enable and route both control and data
information
4. To provide timing circuitry for I/O interfacing
7-47. Decoder circuits are used for which of the
following purposes?
1. Main timing
2. I/O processors
3. Address translation
4. Data buffers
7-48. Status registers are used for which of the
following purposes?
1. To enable and route data using the internal bus
system
2. To hold or buffer data during interchanges
between the very fast CPU and slower
external equipments
3. To hold control data generated by main
memory or the CPU when operating with very
fast external equipments
4. To hold information for the CPU that indicates
the operating condition and current activities
of the external equipments
7-49. In computers with an IOC, once started the master
clock can be stopped when which of the following
actions occurs?
1. Computer master clear
2. External interrupt
3. Input data request
4. Output data request
7-50. In computers with an IOC, the master clock is
started when which of the following actions
occurs?
1. The computer is initially powered on
2. The computer is auto restarted
3. Both 1 and 2 above
4. An execute master clear is issued
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