5.4 Data Buses NEW Flashcards
Wiring utilized to transmit data caries only a negligible current, just sufficient to do what?
Switch a transistor ON or OFF or to carry an audio signal which is then amplified at its destination.
What voltage levels are required for Binary 0?
0 to 0.8V
What voltage levels are required for Binary 1?
2 to 5 Volts
What are the 2 ways of data transfer between systems?
Parallel data transfer and Serial data transfer.
In serial transfer the data is transferred over?
The same line in sequence.
What triggers the transfer of data?
Clock pulses
What is the typical method of speeding up s serial data bus?
Multiplexing
In parallel transfer each bit is taken from?
A separate circuit and is transmitted over a separate line.
What are the advantages of parallel transfer and Disadvantages.
Much faster. Disadvantage = much more hardware, more space and weight.
What are the benefits of multiplexing?
Significant reduction in weight of wires and improved circuit reliability.
How does multiplexing operate?
Via synchronized rotating contacts connecting matching input and output lines in sequence. Data transmitted over the common transmission line.
In reality multiplexing is usually achieved by?
Logic gates responding in sequence to clock pulse signals.
What is the purpose of the shielding on the twisted wire pair?
Spike protection, eliminates EMF, guarantee’s accurate transmissions
What is the purpose of the twisted wire?
Magnetic fields induced by the currents flowing through them will cancel each out out, eliminating EMI
All peripheral components are connected to the highway by?
Breakouts (Couplers)
MIL-STD-1553 defines the term Tim division multiplexing as?
Transmission of information from several signal sources through the same line with different signal samples in time to form a composite pulse train.
Q. What are the the 3 MIL-STD-1553 Data words?
Command words, Data Words, Status Words
What is the length of word for a MIL-STD-1553
20 bits in length.
Q. Define Odd parity
Odd parity means there is always an odd number of 1’s in a word.
Data may travel in one way or in two directions what is this called?
Signal can only travel in 1 Direction = Simplex, 2 ways = Duplex