AET Data Bus Systems and Protocols

Question 1

What is the data transfer rate of ARINC 429 operating in high-speed mode?

Accepted Answer

100 kbps

Answer

ARINC 429 high-speed mode operates at 100 kbps, while its low-speed mode operates at 12.5 kbps.

Question 2

Which data flow topology best describes ARINC 429?

Accepted Answer

Unidirectional point-to-multipoint bus

Answer

ARINC 429 is a unidirectional bus where a single transmitter sends data to up to 20 receivers simultaneously.

Question 3

How many bits are contained in a standard ARINC 429 data word?

Accepted Answer

32 bits

Answer

An ARINC 429 data word is 32 bits long, consisting of an 8-bit label, SDI, data field, SSM, and a parity bit.

Question 4

What does the 8-bit 'label' field in an ARINC 429 word identify?

Accepted Answer

The type or parameter of data being transmitted

Answer

The 8-bit label field identifies the type of data or avionics parameter (e.g., airspeed, altitude) contained in that word.

Question 5

Which encoding scheme is used by ARINC 429?

Accepted Answer

Bipolar Return to Zero (BPRZ)

Answer

ARINC 429 uses Bipolar Return to Zero (BPRZ) encoding with three voltage states: HIGH (+10 V), NULL (0 V), and LOW (−10 V).

AET - Avionics Electronic Technicians Practice Test