30 Questions
What is the maximum number of data words that can be sent in a single transmission in the MIL-STD-1553 bus protocol?
32
What is the purpose of the status word sent by the Remote Terminal?
To indicate that the message was received and was valid
What is the main difference between MIL-STD-1553 and ARINC 429?
MIL-STD-1553 is duplex, while ARINC 429 is simplex
What is the purpose of the command word sent by the Bus Controller?
To define the sub-address of the data and the number of data words
What is the advantage of using microprocessors in avionics systems?
They provide a digital output, negating the requirement for A/D and D/A converters
What is the purpose of the command synchronization word in the RT-RT transmission?
To ignore the command word and wait for the data synchronization word
What is the main difference between MIL-STD-1553 and MIL-STD-1773?
MIL-STD-1553 uses electrical cables, while MIL-STD-1773 uses fibre optic cables
What is the purpose of the data synchronization word in the RT-RT transmission?
To indicate the start of the data transmission
What is the disadvantage of using A/D and D/A converters in avionics systems?
They increase the cost of installations
What is the advantage of using the MIL-STD-1553 bus protocol?
It is duplex, allowing data to flow in both directions
What is the primary purpose of the MIL-STD-1553 data bus?
To provide a common medium for the exchange of data between systems
What is the synchronization field used for in the MIL-STD-1553 word format?
To allow all device clocks to re-sync at the beginning of each new word
What type of encoding is used for all words in MIL-STD-1553?
Bi-Phase Manchester II
What is the purpose of the parity bit in the MIL-STD-1553 word format?
To ensure odd parity for the single word
What type of transmission is used when the BC commands a mode change of an RT without any data being transferred?
Mode change transmission
What is the purpose of the status word in the MIL-STD-1553 message format?
To validate the receipt of the message by the RT
What is the primary function of MIL-STD-1553 data bus?
To allow multiple avionics units to share a single set of wires and transmit data
What is the total number of bits in a MIL-STD-1553 word?
20 bits
What type of signal transitions occur in the MIL-STD-1553 bus?
A logic 0 is a signal that transitions from a negative level to a positive level, and a logic 1 is a signal that transitions from a positive level to a negative level
What is the term defined by MIL-STD-1553B as 'the transmission of information from several signal sources through one communications system with different signal samples staggered in time to form a composite pulse train'?
Time Division Multiplexing (TDM)
What is the purpose of the word count in the command word?
To specify how many data words are about to be sent or received
What was the primary user of the initial MIL-STD-1553 standard released in August 1973?
F-16 Fighting Falcon
What is the philosophy behind the information transfer formats in MIL-STD-1553?
Command/response philosophy
How many years did the Society of Automotive Engineers (SAE) spend to produce MIL-STD-1553B?
3 years
What is the main reason why the government decided to 'freeze' the standard at the B level?
Both A and B
What are the three distinct word types defined by the MIL-STD-1553 standard?
Data words, Command words, and Status words
What is the main advantage of using a data bus in avionics systems?
Reduced system complexity and weight
What is the term used to describe the transmission of data between multiple avionics units over a single transmission medium, with the communications between the different avionics boxes taking place at different moments in time?
Time Division Multiplexing (TDM)
What is the primary purpose of the MIL-STD-1553 data bus?
To allow multiple avionics units to share a single set of wires and transmit data
When was the tri-service version, MIL-STD-1553A, released?
1975
Study Notes
MIL-STD-1553 Data Bus
- MIL-STD-1553 is a military standard that defines the electrical and protocol characteristics for a data bus.
- The standard was released in August 1973 and was primarily used by the F-16 Fighting Falcon.
- The standard allows multiple avionics units to share a single set of wires, enabling data transfer between units.
Data Transmission
- MIL-STD-1553 uses Time Division Multiplexing (TDM) to transmit information from multiple signal sources through one communications system.
- Data is transferred between multiple avionics units over a single transmission medium, with communications taking place at different moments in time.
Data Words
- There are three distinct word types defined by the standard: Command words, Data words, and Status words.
- Each word is 20 bits in length, with a synchronization field, information field, and a parity bit.
- The information field differs between the three word types.
Command Words
- Contain a terminal address, T/R bit, sub-address mode, and word count.
- Used to command a remote terminal to receive or transmit data.
Data Words
- Contain purely data and are always preceded by a command or status word.
- May contain up to 32 data words.
Status Words
- Contain the terminal address, indicating that the data transfer was completed successfully and the remote terminal is serviceable.
Data Transfer
- There are 10 types of message transmission formats, including mode change, broadcast, and information transfer formats.
- The Bus Controller (BC) sends command words to Remote Terminals (RTs) to initiate data transfer.
- RTs respond with status words to validate the receipt of the message.
Remote Terminal to Remote Terminal (RT-RT) Message
- Allows a terminal to transfer data directly to another terminal without going through the BC.
- The BC issues command words to both the receiving and transmitting terminals.
MIL-STD-1553B
- Released in 1978, it is an improved version of the standard that allows for more definitions and capabilities.
- The government froze the standard at the B level to allow component manufacturers to develop products and gain real-world experience.
MIL-STD-1773
- Contains the requirements for utilizing a fibre optic 'cabling' system as a transmission medium for the MIL-STD-1553B bus protocol.
- The standard repeats MIL-STD-1553 nearly word-for-word, but with differences in pulse definitions and environmental considerations.
Learn about MIL-STD-1553, a military standard defining electrical and protocol characteristics for a data bus, enabling systems and subsystems to share a single set of wires.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
