ET VOL 6 CH 7 CONT Flashcards
The read/write control logic accepts control signals from which of the following devices?
- The control bus
To program the USART for the applicable interface when it is in an idle state, which of the following signals/words is required?
- A new set of control words
The universal synchronous-asynchronous receiver transmitter is enabled for reading/writing operations when which of the following signals is true?
- The CHIP SELECT
When the WRITE DATA (WD) signal is true, it means which of the following things?
It indicates the microprocessor is placing data on the data bus
When the READ DATA (RD) signal is true, the microprocessor is ready for which of the following activities?
- To receive data and status words
The transmit control logic converts the data bytes stored in the transmit buffer into which of the following forms?
- An asynchronous bit stream
A start bit is used for which of the following purposes?
- To alert the output device
A parity bit is used for which of the following purposes?
- To detect errors
The receive buffer stores which of the following information?
- Parallel bytes
The voltage and current characteristics of line drivers/receivers are dictated by which of the following factors?
Type of circuitry (TTL or MOS
Type A (NTDS) Slow interface format is able to transmit which of the following number of bit groupings?
16, 30, or 32, depending on the type of computer
The data transmission rate for Type A (NTDS) Slow format is limited by which of the following factors?
The large voltage change between logic states
In Type D (NTDS SERIAL) interface format, information frames are made up of what total number of bits?
32 bits
Type D (NTDS SERIAL) interface format can transmit digital signals up to which of the following lengths?
1000ft
Type E (NATO SERIAL) format requires which of the following I/O cables?
Triaxial
Type E (NATO SERIAL) format is most frequently used with which of the following equipment?
Mainframe computers
Type F (aircraft internal time division multiplex [TDM] bus) interface format transmits bit groupings consisting of what total number of bits?
20
Type F (aircraft internal time division multiplex [TDM] bus) interface format can handle which of the following numbers of external devices on one channel?
32 (including a bus controller
Type G (RS-449) interface format primarily uses which of the following protocols?
- Command and response
The Small Computer System Interface (ANSI X3.131) using one controller can daisy chain up to what maximum number of units?
8
The RS-232 interface can be used for which of the following types of transfers?
- Asynchronous and synchronous serial
The RS-232 interface can be used with which of the following types of computers?
- Micros, minis, and mainframes
The RS-232 interface limits cable transfers to what maximum number of feet?
50ft
In the RS-232 interface, most peripherals control configuration parameters using which of the following methods?
dip switches
The higher transmission rate of the RS-422 interface is made possible by which of the following techniques?
- Two separate wires are used 2. The receiver transition period is narrower 3. The grounding requirements are less critical
In a token ring network, a station with a message waits until it receives a free token, it then changes the free token to a busy token, and transmits a block of data following the busy token. What term is used for the block of data?
frame
The Ethernet interface is used to transfer which of the following types of data in what format?
- Serial I/O data in packet format
The type of cable used for the Ethernet interface is which of the following?
- Shielded coaxial
Thin Ethernet interface used in smaller systems can have a maximum cable length of which of the following?
1000ft
The Centronics Compatible Parallel interface uses which of the following types of protocol?
- Command/acknowledge
Most floppy disk drives today are controlled by which of the following interfaces?
- ST-506/412 interface
When using the ST-506/412 interface, the controller card performs which of the following functions for disk drives?
- Moves the magnetic head 2. Spins the magnetic disk 3. Strips off formatting and control words
When using the ST-506/412 to interface a hard disk drive, the cabling required is which of the following?
- A 34-pin control cable 2. A 20-pin data cable
When using the ST-506/412 to interface a floppy disk drive, the cabling required is which of the following?
34-pin control cable
The enhanced small device interface can transfer data at up to which of the following rates?
24 megabits per second
When using the enhanced small device interface with a floppy disk drive, the cabling required is which of the following?
- A 34-pin control cable 2. A 20-pin data cable
All electronics used for the integrated drive electronics interface are located in which of the following areas?
The hard drive
The integrated drive electronics interface can handle disk drives with a maximum capacity of which of the following?
300 MB
The minimum number of conductors required for I/O serial data operations is which of the following?
4
During asynchronous data exchange, a frame of data must include which of the following bits at a minimum?
- One start bit 2. One stop bit 3. Seven character bits
During asynchronous data exchange, the maximum number of bits for one frame of data is which of the following?
11
Compared to asynchronous data exchange, synchronous data exchange has which of the following advantages?
Faster speed
The generally accepted standard connector for implementing an RS-232 connection has what total number of pins?
25
The protective ground, pin 1 of the RS-232 interface connector in the DTE/DCE mode should always be connected to the shielded cable shield at both ends.
false just one side
Pin 7 of the RS-232 interface connector in the DTE/DCE mode should always be connected at both ends for which of the following reasons?
To complete the path for control signals only
Pin 3 of the RS-232 interface connector in the DTE/DCE mode is used for which of the following purposes?
To receive data signals
Pins 4, 5, 6, and 20 are used in the DTE/DCE mode using the RS-232 interface connector for which of the following purposes?
To establish the communications link (pin 4-send)(pin 5 clear to send)(pin-6 data ready set)(pin 20 data terminal reads)
In parallel data operations, the IOA or line driver/receiver provides the means to accomplish which of the following tasks?
- Drive or detect the digital signals
In parallel data operations, one I/O channel could consist of which of the following devices?
- Two cables, one for input and one for output or a single cable to handle both input and output 2. Eight or more data lines 3. A number of control lines
The data strobe in single parallel cable operations is used for which of the following purposes?
Signals the external device that data is ready to be read from the data lines
In single parallel cable operations, a busy signal would be sent under which of the following conditions?
The external equipment input buffer is full
In two cable parallel operations, an external interrupt enable can be described as which of the following?
A signal sent from the computer on the input line
When an external interrupt code is placed on the data lines, it is accompanied by which of the following signals?
- An external interrupt request
In a two cable sequence of events for input data, the first event will be which of the following?
The external equipment places a word of data on the ID lines
In the two cable sequence of events for input data, the computer has sampled the data on the ID lines. Which of the following events must occur before the computer will accept more data?
- The IDR must be cleared
During a normal external function sequence of events, the computer places an EF code word on the OD lines. The next event to take place is which of the following?
- The EFR line is set External Fuction Ready
During forced external functions, the computer does not require which of the following signals?
EFR External Fuction Ready
During the external interrupt sequence of events, what is the first event that must occur before a computer will accept an external interrupt?
The EIE line is set
All computers used by the Navy will have EIE lines.
false
In intercomputer I/O operations when parallel channels are used, the input and output cables will have which of the following characteristics?
The input and output cables will be identical
During intercomputer I/O operations, command words include which of the following data?
External functions, forced external functions, and external function buffer words
During intercomputer I/O operations, command word functions are identified by use of which of the following techniques?
- Additional interface signals
For an intercomputer command word buffered transfer, the receiving computer is ready to accept an external function command word. This is signaled by which of the following means?
The external interrupt enable line is set
During an intercomputer command word buffered transfer, before putting the EF code on the data lines, the transmitting computer recognizes which of the following signals?
EFR External Function Ready
In intercomputer I/O operations, all command words specified by the receiving computer’s EF buffer control words will be transferred one command word at a time.
true
Before the intercomputer data transfer sequence of events can begin, which of the following events must have occurred on the same channel?
- An OD buffer must have been established on the transmitting computer 2. An ID buffer must have been established on the receiving computer
In intercomputer data transfers, the data word is held on the OD lines until the receiving computer performs which of the following tasks?
- Sets the resume line
In intercomputer data transfer, the receiving computer recognizes the ready line of the transmitting computer as what line?
- The IDR line
In intercomputer data transfer, the transmitting computer recognizes the IDA line of the receiving computer as what line?
The resume line
In intercomputer data transfer, after one data word has been transferred and before the next data word is placed on the data OD lines, which of the following events occurs?
- The receiving computer sets the IDA line 2. The transmitting computer clears the ready line