16.0 How Your DB150 Manages 22 Addresses
16.1 22 “Slots” For Addresses
The DB150 command station can run up to 22 loco addresses and throttles at a
time. Each of these addresses occupies one of 22 “slots” available in the
DB150’s memory. Once those 22 slots are full the system will display the
“slot=max” message to let you knot that you need to release some locos if you
want to select and run others. The DB150 manages the addresses that occupy
slots by assigning different statuses to each decoder depending on how it is
being used in the system. This allows the DB150 to automatically remove, or
purge, addresses to make room for other locos to be selected and run.
There are two factors that determine the status of each decoder: whether or not
it is selectable and whether or not the command station is refreshing it.
Decoder addresses are selectable if they are not being used by any throttle in
the system. When your command station is running a loco on an address, it
sends commands and refreshes those commands. The 22 address limit is the
number of addresses that your DB150 can refresh at the same time. When the
command station refreshes data sent to decoders, it is just repeating previously
issued commands. The reason for this is to be sure that the decoders don’t for-
get what they are supposed to be doing. For example, if your decoder encoun-
ters a power interruption caused by dirty track, it is momentarily out of contact
with the command station and it might lose the DCC signal. By refreshing the
decoder’s data, the command station makes sure everything keeps running
smoothly.
Your Digitrax system classifies decoders as follows:
Purging of addresses:
Purging is the process by which the DB150 changes the status of decoders that
are either not being used or are unattended to make room for other addresses to
be selected and refreshed by the command station.
If a
DT400 with selected in-use locomotives
is unplugged from LocoNet for
more than about 3 1/4 minutes, the command station will change the status of
these in-use locomotives to common so that they are available for selection by
other throttles in the system. When this happens you will hear three beeps from
the DB150.
When the DT400 that has been purged is plugged in again, it will attempt to
Decoder Status
Selectable
Refreshed
New or Idle
Y
N
In-use
N
Y
Common
Y
Y
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