Digital Techniques in Aviation

Questions and Answers

What is the primary function of the Remote Terminal to Remote Terminal (RT-RT) command?

To transfer data through the Bus Controller (BC)

To enable direct data transfer between two terminals (correct)

To validate data before transmission

To synchronize command words between terminals

What action does the receiving terminal take after receiving a command synchronisation word?

Processes the command without delay

Sends a request back to the transmitting terminal

Transmits its status word immediately

Ignores the command sync and waits for data sync (correct)

How does the transmitting terminal respond if the first command word doesn't contain the appropriate terminal address?

It immediately transmits data words

It ignores the first command word (correct)

It sends a status word to the BC

It encounters a communication error

What type of command does the transmitting terminal process if the second command word is addressed to it?

RT-BC command Signup and view all the answers

What initiates the process of data collection in the receiving terminal?

The presence of a data sync word Signup and view all the answers

What does the terminal transmit after receipt and validation of all data words?

Its status word Signup and view all the answers

In the context of the 1553 bus, what does 'bidirectional' mean?

Data can flow in both directions, but not at the same time Signup and view all the answers

Which component may collect data during RT-RT command transmissions?

The Bus Controller (BC) Signup and view all the answers

What conveys information on the MIL–STD–1553 bus?

Timing and polarity of zero crossings Signup and view all the answers

Which message transmission format does NOT involve data being transferred?

BC commands mode change of RT, without any data being transferred Signup and view all the answers

How many primary types of message transmission formats are defined in the MIL–STD–1553 standard?

10 Signup and view all the answers

What is the role of the BC in the bi-phase waveform communication?

To command and transmit data to RTs Signup and view all the answers

Which of the following is NOT a type of Mode change transmission?

BC broadcasts data to multiple RTs simultaneously Signup and view all the answers

Why is the 1553 bus considered forgiving of voltage level variations?

Information is based on timing rather than voltage magnitude Signup and view all the answers

Which of the following best describes a Broadcast message transmission?

Data transmitted from BC to RTs Signup and view all the answers

What is a key characteristic of the zero crossings in the 1553 bus?

They represent logical highs and lows in communication Signup and view all the answers

What is the primary function of the ARINC 629 data bus?

To provide a time-division multiplex communication method Signup and view all the answers

Which aircraft served as the test bed for the new data bus technology?

Boeing 737 Signup and view all the answers

What was the maximum transmission rate of the ARINC 629 data bus?

2 Mbps Signup and view all the answers

How many users can the ARINC 629 data bus support?

120 users Signup and view all the answers

What event marked the formal adoption of the ARINC 629 specification?

September 1989 Signup and view all the answers

Which component directly interfaces with the stub cable in the ARINC 629 system?

Serial Interface Module (SIM) Signup and view all the answers

What ensures only one terminal transmits at a time in the ARINC 629 system?

Protocol timers Signup and view all the answers

What technology was the basis for the ARINC 629 data bus standard?

DATAC technology Signup and view all the answers

What is the primary function of the handshaking principle in information transfer formats?

To validate the receipt of a message by the remote terminal Signup and view all the answers

What does the command word sent by the Bus Controller specify?

The memory location for data storage Signup and view all the answers

Which message is referred to as the receive command?

Bus Controller to Remote Terminal (BC-RT) Signup and view all the answers

After validating the command word, what does the Remote Terminal send next in the RT-BC message?

A status word followed by the requested data words Signup and view all the answers

What is the maximum number of data words that can be specified in a command word?

32 Signup and view all the answers

What type of command does a Bus Controller issue to receive data from a remote terminal?

Receive command Signup and view all the answers

How does the Remote Terminal confirm its receipt of the transmitted data from the Bus Controller?

By issuing a status word Signup and view all the answers

What is the purpose of the Bus Controller in the information transfer process?

To initiate and manage the data transmission process Signup and view all the answers

What is the key difference between the 1553 data bus and the ARINC 429 data bus in terms of data transfer signaling?

ARINC 429 uses Return to Zero (RTZ) coding. Signup and view all the answers

How many receivers can be connected to a single ARINC 429 transmitter?

Up to 20 receivers. Signup and view all the answers

What is the primary format of data transmission in ARINC 429?

A single 32-bit data word or a NULL state. Signup and view all the answers

What is indicated by the label field within an ARINC 429 data word?

The type of data contained in the word. Signup and view all the answers

Which statement correctly describes the communication method of ARINC 429?

It uses a point-to-point protocol. Signup and view all the answers

How does ARINC 429 ensure effective communication among components?

Through the synchronization of all components. Signup and view all the answers

What is the fundamental requirement for components using ARINC 429 for successful communication?

They should speak the same language and be synchronized. Signup and view all the answers

What methodology does the ARINC 429 system use for signaling?

Return to Zero (RTZ) signaling. Signup and view all the answers

Study Notes

Data Transfer Techniques in Aviation

1553 Bus Signaling: Information transmitted via timing and polarity of zero crossings; magnitude of voltage is not significant.
Forgiving Conditions: 1553 bus withstands variations in voltage levels without affecting signal integrity.

MIL-STD-1553 Message Formats

Primary Purpose: Facilitates data exchange between systems using defined message transmission formats.
Message Types:
- Mode change messages for altering the state of remote terminals (RT).
- Broadcast message transmissions for data dissemination from bus controller (BC) to multiple RTs.
- Information transfer formats based on command/response philosophy ensuring error-free transmissions.

Bus Controller to Remote Terminal (BC-RT)

Receive Command: BC sends command word to specify data sub-address and the number of data words (up to 32).
Status Word: After validating data receipt, the RT sends a status word back to the BC.

Remote Terminal to Bus Controller (RT-BC)

Transmit Command: RT responds by sending its status word followed by requested data words upon BC command validation.

Remote Terminal to Remote Terminal (RT-RT)

Direct Data Transfer: Enables one RT to send data directly to another without going through BC.
Command Synchronization: Receiving RT must ignore any unwanted command words until the correct data synchronization is established.

Bidirectional Nature

Data Flow: The 1553 bus allows bi-directional data transfer, but not simultaneous.

ARINC 429 Data Transfer

Manchester II Bi-Phase Coding: Data represented by signal polarity shifts, ensuring independence from voltage levels.
RTZ Signaling: ARINC 429 uses Return to Zero, where a voltage of 0 denotes no signal.

ARINC 429 Protocol Characteristics

Point-to-Point: Employs a single transmitter with multiple receivers on a wire pair.
Message Structure: Predominantly single 32-bit data words with labels defining data types.

ARINC 629 Specifications

Time-Division Multiplexing: Supports up to 120 users at 2 Mbps; ensures only one terminal transmits at a time.
Utilization of Quiet Periods: Terminals must wait for quiet periods to avoid transmission conflicts.
Coupler and Terminal Interface: Inclusion of a Serial Interface Module (SIM) within each Line Replacement Unit (LRU) for connection to the global data bus.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the key concepts of digital techniques and electronic instrument systems in aviation. This quiz focuses on the Manchester II Bi-Phase waveform and its relevance to voltage levels and signaling. Ideal for those studying CASA Part 66 materials.

Digital Techniques in Aviation - Bi-Phase Waveform