Welcome Back

Sign in to your PART66Online account

or use email
Forgot password?

Don't have an account? Register here

Module 5. Digital techniques / Electronic instrument systems

In an Arinc 429 Word label-representing heading is 320, this is represented in bits 1- 8 as

  • 01011001.
  • 00001011.
  • 01101000.

hasdim_1969 asking:

HOW???

Community Comments (7)

D
dimky Posts: 514 25.12.2012 / 21:51
320 should be converted to octal and reversed because MSB transfered first.
H
hasdim_1969 Posts: 3 27.12.2012 / 14:04
thanks
J
JD2016 Posts: 54 29.05.2017 / 19:28
A load of 1's and O's is hardly Octal!
D
dimky Posts: 514 30.05.2017 / 09:59
JD2016, you think something is wrong here?
J
JD2016 Posts: 54 31.05.2017 / 22:27
Yes! If as you say, 320 should be converted to Octal, then 320 in octal is 500. A string of 1's and 0's is obviously Binary. I understood that an ARINC 429 word was written in Binary anyway. See EHJ Pallett - Aircraft Instruments & Integrated Systems - 3rd Edition Page 159 - Figure 6.4.
:)
D
dimky Posts: 514 31.05.2017 / 23:10
Not like this. In ARINC429 label is binary coded octal (8 bits):
000 010 11 = 0 2 3
You have to divide label by 3 and 3 and 2 bits. And then convert each set to octal.
Inversed because usually arinc429 word is represented in reverse order because label is transmitter MSB first but data LSB first. Question is a little bit miss-worded but still the only possible option is B.
Very detailed explanation here: http://aviftech.com/files/2213/6387/8354/ARINC429_Tutorial.pdf
J
JD2016 Posts: 54 31.05.2017 / 23:50
Thanks.
It really is designed to confuse!

Please Sign In to post a comment.

We use essential cookies to keep you signed in, plus anonymous analytics to understand how the site is used. Cookie-based analytics is set only with your consent. See our Privacy & Cookie Policy.