Lesson 9 : Network Components Part 2 Flashcards
which controls the flow of information in a multipoint data link system.
Line Control Unit (LCU or LinCo )
the primary station, the LCU is often called a _______ because it processes information and serves as an interface between the host computer and all the data communications circuits it serves.
Front-End Processor
directs the flow of input and output data between data communications circuits and their respective application programs.
FEP
inserted and deleted in the FEP and LCUs
Data-Link Control Character
A single special purpose integrated circuit performs many of the fundamental data communications functions and is designed for asynchronous data transmission
Universal Asynchronous Receiver/Transmitter (UART)
A single special purpose integrated circuit performs many of the fundamental data communications functions and is designed for synchronous data transmission
Universal Synchronous Receiver/Transmitter (USRT)
A single special purpose integrated circuit performs many of the fundamental data communications functions and is designed for asynchronous or synchronous data transmission
Universal Synchronous/Asynchronous Receiver/Transmitter (USART)
DIP
Dual in-line Package
USARTs are available in __- to __-pin dual in-line packages
24 to 64
DTE
Data Terminal Equipment
DCE
Data Communications Equipment
Special purpose UART chip manufactured by Motorola
Asynchronous Communications Interface Adapter (ACIA)
allows UART to operate virtually independently of one another
Bidirectional Data Bus
coordinates data transfer between
the line-control unit and the modem
CPU
responsible for programming the UARTβs
control register, reading the status register,
transferring parallel data to and from the
UART transmit and receive buffer register
CPU
specifies the number of data bits per character
Control Word
only bit in the UART that is not
optional or programmable.
Start Bit
an n-bit data register that
keeps track of the status of the UARTs
transmit and receive buffer registers
Word Register
transmit shift register has been completed
transmission of a data character
Transmit Buffer Empty (TBMT)
set when a received character has a parity error in it
Receive Parity Error (RPE)
set when a character is received without any or with an improper number of stop bits
Receive Framing Error (RFE)