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What is the encoding difference between ARINC 429, BNR v.s.and BCD formats?

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I think I have an understanding of the differences between the types of ARINC word formats, but would just like to get some input to see if my understanding is correct. In the ARINC 429 specification, it is discussed that there are some differences in how messages are handled between the two formats.

Data Field

This one just seems like basic arithmetic concepts and doesn't concern me as much. From what I understand, the BCD data-field works the following way:

Data-Field = 0x12340, means that the data is actually 12,340 (twelve thousand, three-hundred-forty) in base-10.

Then, BNR data-field would work like:

Data-Field = 0x7FD1C, means that the data is actually -740 (based on two's complement arithmetic).

Sign-Status Matrix Field

The operational codes just mean different things. Or in other words, the code numbers are the same, but the codes themselves have different meanings for BCD messages than BNR ones. Now, if there aren't any other differences, I would also like to know why the op-code schemes are slightly different.

My Question

So, I guess in a single sentence my question would be: are these the only differences between the types of ARINC messages?

I think I have an understanding of the differences between the types of ARINC word formats, but would just like to get some input to see if my understanding is correct. In the ARINC 429 specification, it is discussed that there are some differences in how messages are handled between the two formats.

Data Field

This one just seems like basic arithmetic concepts and doesn't concern me as much. From what I understand, the BCD data-field works the following way:

Data-Field = 0x12340, means that the data is actually 12,340 (twelve thousand, three-hundred-forty) in base-10.

Then, BNR data-field would work like:

Data-Field = 0x7FD1C, means that the data is actually -740 (based on two's complement arithmetic).

Sign-Status Matrix Field

The operational codes just mean different things. Or in other words, the code numbers are the same, but the codes themselves have different meanings for BCD messages than BNR ones.

My Question

So, I guess in a single sentence my question would be: are these the only differences between the types of ARINC messages?

I think I have an understanding of the differences between the types of ARINC word formats, but would just like to get some input to see if my understanding is correct. In the ARINC 429 specification, it is discussed that there are some differences in how messages are handled between the two formats.

Data Field

This one just seems like basic arithmetic concepts and doesn't concern me as much. From what I understand, the BCD data-field works the following way:

Data-Field = 0x12340, means that the data is actually 12,340 (twelve thousand, three-hundred-forty) in base-10.

Then, BNR data-field would work like:

Data-Field = 0x7FD1C, means that the data is actually -740 (based on two's complement arithmetic).

Sign-Status Matrix Field

The operational codes just mean different things. Or in other words, the code numbers are the same, but the codes themselves have different meanings for BCD messages than BNR ones. Now, if there aren't any other differences, I would also like to know why the op-code schemes are slightly different.

My Question

So, I guess in a single sentence my question would be: are these the only differences between the types of ARINC messages?

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