What are the basic components of an ARINC 429 data word?

What are the basic components of an ARINC 429 data word?

• A. A 64-bit word with data and CRC.
• B. A 32-bit word consisting of a label, data field, and a parity/check bit.
• C. A 16-bit word with address and status bits.
• D. A 24-bit word with header and payload.

Answer: (B)

ARINC 429 uses a fixed 32-bit word divided into three parts: an 8-bit label that identifies what parameter or data type is being sent, a data field that carries the actual value, and a parity bit that provides simple error detection for the word. The label acts as the address so receivers know how to interpret the data field, while the parity bit helps detect single-bit transmission errors. This structure—32-bit word with label, data, and a parity bit—best fits the standard, whereas the other descriptions describe different sizes or omit the parity mechanism, so they don’t match ARINC 429.

ARINC 429 uses a fixed 32-bit word divided into three parts: an 8-bit label that identifies what parameter or data type is being sent, a data field that carries the actual value, and a parity bit that provides simple error detection for the word. The label acts as the address so receivers know how to interpret the data field, while the parity bit helps detect single-bit transmission errors. This structure—32-bit word with label, data, and a parity bit—best fits the standard, whereas the other descriptions describe different sizes or omit the parity mechanism, so they don’t match ARINC 429.