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5.3.3 Start-up behavior
When the Command Station powers up, it emits for approximately 1 second alternating DCC Broadcast
Digital DecoderReset commands, and M/M Broadcast Speed Zero commands. This ensures that there are
no runaway locomotives without the control of a throttle. Afterwards the regular (idle) packet sequence
takes over.
In order for this start-up sequence to be effective, we recommend powering up the boosters of a layout first,
then the command station.
5.3.4 Packet prioritization and repetition
The CS-105 prioritizes packets to locomotives to achieve the best combination of fast response and
reliability. Upon a change on a throttle (such as changing the speed or turning a function on and off),
high-priority packets are going to be emitted to the track as soon as possible; then later low-priority packets
are going to repeat this information; finally, refresh packets are going to keep repeating the locomotive state
forever.
Refresh packets are emitted for DCC decoders for speed and functions F0-F12; for M/M decoders speed
and F0-F4.
The DCC bandwidth usage can be viewed in the Status screen, aggregated to a 10-second window and a
10-minute window.
5.3.5 RailCom®-enabled DCC decoders
RailCom-enabled locomotives do not need packets to be repeated, therefore saving a significant amount of
DCC bandwidth. We recommend using RailCom-enabled locomotives, deploying RailCom-enabled
Boosters such as the TCS B-106, and enabling RailCom channel 2 transmissions in the decoders (CV28 bit
2 = 1).
The number of currently operating RailCom-enabled locomotives can be viewed in the Status screen.
5.3.6 Heartbeat
The CS-105 can continuously verify that a throttle controlling a moving train is operational, recognizing and
stopping runaway trains that may be due to throttle malfunctions, dead batteries, wiring or wireless issues.
This is accomplished by sending the throttle an LCC message, which it shall automatically or manually
respond to, indicating that it is alive and intending to control that locomotive. A stopped train never
generates heartbeat messages. When a throttle releases a train, the heartbeat checking also stops. For
each train only the last assigned throttle will be checked.
A configuration option in DCC System Settings > Advanced Settings controls this feature. Setting the option
to zero disables throttle heartbeats.
5.3.7 Speed mapping
The CS-105 translates the speed steps of the selected DCC or M/M protocol to the scale speed of 0 to 126
mph reported to the LCC throttles. This means that even if a decoder is driven with 14 or 28 speed steps,
the throttles will always appear at 126 mph maximum speed.
The recommendation is that for speed matching purposes the locomotive decoders should be configured
with a speed table that defines 1 (of 126) speed steps as 1 scale mph; for example, calibrate the locomotive
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