BondedSidings
Background
In territories that have single-track with sidings, it is very common that the sidings are "non-bonded", which essentially means that they are not connected to the signal system to display train occupancy. This will give the illusion in ATCSMonitor that the train "disappears" into the siding, and then "reappears" on the other side. The railroads CTC software at the dispatching center had enough other data on train movement that it can reflect the siding as occupied within software. These are usually displayed in a different color to reflect that a train is present, however, isn't "sensed" by the signal system.
Solution
In order to simmulate this behavior in ATCSMon, VBScripting is used. Below is an example from the Aurora Sub layout on how it works:
At Big Rock W (x):
x:LA=If RW AND T Then LA = True [[ElseIf|Else If]] (RW AND EA) Or (vXRW AND vXWA) Then LA=False End If
At Big Rock E (X):
X:LA=If RW AND T Then LA = True [[ElseIf|Else If]] (RW AND WA) Or (vxRW AND vxEA) Then LA=False End If
Then, here's the "glue" that makes it all work:
X:RA=If vxLA OR vXLA Then RA = True else RA = False
Sooooo... the "pseudo-bonded" siding is labeled X:RA in this case, it "guesses" that a train is there based on receiving a RW&WA, or a RW&EA from the stations at either end of the siding.