Step 10: Floobydust - Configuring Tsunami’s Miscellaneous Features
F11 Train Brake
By now you’ve no doubt discovered that Function F11 can be used to turn Tsunami’s brake squeal sound on and off. What you may not realize is that F11 can also be used to slow your train down as if the brakes really are applied!
To achieve this effect, you will need to first program some momentum into Tsunami using CV 3 and CV 4 to set the acceleration and braking rate respectively. The exact value is unimportant but should be large enough to produce a noticeable delay in the throttle response. A setting of 20 or so will do the trick. The reason for programming CV 3 (acceleration rate) is so the train does not immediately resume its old speed when the F11 function is released.
Next, program CV 61 (F11 Brake Rate) to adjust the rate at which the train will slow down when F11 is turned on. A value of 1 to 128 is added to the value programmed in CV 4 which has the effect of slowing the train more gradually than by simply turning the throttle down. Values of 129 thru 255 translate to -1 thru -127 which have the opposite effect as they subtracted from the setting in CV 4 and slow the train more aggressively than turning the throttle down (as a brake would be expected to do).
Be careful not to set F11 too high - if you do, the net braking rate will be zero and you will have effectively turned F11 into an emergency stop button!
Note that setting CV 61 to a value of 0 or 128 has no effect on the brake rate and basically disables this feature.
The DC Braking feature allows you to configure Tsunami to bring the locomotive to a gentle stop whenever DC power is present on the track. In this manner you can implement an inexpensive ‘braking section’ for stopping locomotives in front of a red block signal. This is done by using a relay or other switch to supply a section of track ahead of the signal with DC when the signal is red and DCC power when the signal is green. Then, configure Tsunami decoder as follows:
Set CV 11, Packet Time Out Value. CV 11 determines the amount of time, in 0.25 second increments, that elapses between when Tsunami first detects the loss of the DCC control signal and when it begins to bring the locomotive to a stop. For DC Braking, we suggest using a small value of 1 or 2 corresponding to a detection time of a 1/4 to 1/2 second.
Set CV 3 (Acceleration Rate) and CV 4 (Braking Rate). Since you won’t want your train to come to a sudden stop, you’ll need to set these CVs so
Tsunami Steam Sound User’s Guide