Distinctive attribute of ARINC 629

Question

The distinctive attribute of ARINC 629 says that access to the bus in order to transmit through the given terminal is based upon meeting the three timing conditions. Name them.

Answer 1

The three timing conditions are:

a) Transmit Interval (TI),

b) Terminal Gap (TG) and

c) Synchronization Gap (SG).

Transmit Interval (TI) refers to a global Bus Parameter. For the particular terminal, TI initiates moment the terminal begins transmitting. Once it has transmitted, it should wait for the length of time given by the TI before it may transmit again (0.5 to 64 ms).

Terminal Gap (TG) refers to a unique timer allocated to every terminal upon the Bus. TG is initiated only after SG has elapsed and only in case no carrier is present. TG and SG may not overlap in time; they should run consecutively (4 to 128 µs).

Synchronization Gap (SG) refers to the global access parameter. SG refers to the second longest timer and is set to the same value in all the terminals. SG begins the moment the bus is quiet, it is reset if the carrier emerges over the bus before it gets elapsed.