The Perils of Programming (the Tsunami2 Steam Decoder, step-by-step)

While the title of this post may remind you of that fun serial from yesteryear, thankfully programming a DCC decoder won't kill you. But after going down the rabbit hole of DCC programming, you may feel a little like you got hit by a train.

 

See what I mean?

Believe it or not, I started working on New Haven K-1d #359 shortly after I got it back during the Springfield show last January (which seems an eternity ago). The engine was perfect mechanically, but the TCS decoder in it was an older decoder and the motor control was erratic. A new TCS decoder didn't improve things much, so by the time summer rolled around I decided to try a Tsunami2. A quick swap-out improved things dramatically, but unfortunately while I was doing the final install, I managed somehow to fry it. That was in August. Thankfully, my friend KayleeZ hooked me up with a replacement decoder, which - having learned a lesson or two along the way - I installed this time with no problems.

But installing the decoder is only the first step. Sure, you could just accept the factory default settings, but what fun is that - especially when you've worked on a steam locomotive and have your own ideas of how you want it to sound?

Admittedly, the Tsunami2 sounds great right out of the package. But one thing the folks at Soundtraxx can't do for you is set the chuff rate to match your specific locomotive. You've got to do that yourself. So, back in September I started doing just that (and that's what's going on here).

Unfortunately, things have gone a bit sideways during the past almost-three-months (in both good, as well as not-so-good ways), so I'm just now getting back to this programming project - and wanting to finally finish before it gets to be a FULL YEAR before the #359 is back in service(!).

Since I'm a bit anal OCD thorough with such things (see pic above), I read through the Tsunami2 Steam User's Guide, the Technical Reference manual, and the Sound Selection Reference. Since my main goal was to get the chuff rate dialed in, I also checked out Soundtraxx's great video on that here. I even bugged George Bogatiuk quite a bit about it - and he was very patient and super helpful answering all my questions.

I have a hard-wired cam on my other Tsunami1-equipped K-1 moguls, but unfortunately, the Tsunami2 doesn't have that capability and uses a "digital" cam instead. Long story short, you adjust CV114 to get the engine to chuff 4 times per driver revolution and, once set, the decoder is supposed to match that rate to the turning of the motor and thus have the chuff rate be correct through all speed steps.

I'll get right to the punch line: It took me a lot of fiddling and I still don't think I have it as perfect as I'd like (or as perfect as the hard-wired cams), but it's very good and MUCH better than the old throttle/speed step-based chuff synch. If you don't already have a cam installed on your engine - or even if you do and don't feel like wiring it - the Tsunami2 gets you 90% there, IMO. And that's close enough for most folks - especially when you consider all of the other new features in the Tsunami2 vs. the Tsunami1.

As for the general decoder programming itself, I've included it below 1) as a reference for the future, and 2) as an invitation to you all to let me know how you'd do it differently . . .

1. Did a full/clean factory reset of the decoder.
2. Read the values from the decoder into JMRI's DecoderPRO.
3. Saved that file as a master.
4. Changed the long address from "3" to "359"
5. Reduced the Master Volume (CV128) from 192 to 80 (didn't want to risk the amp in the new decoder blowing out my old speaker).
6. Momentum Settings
1. Set Acceleration Rate (CV3) to 150
2. Set Deceleration Rate (CV4) to 255
7. Function Map
1. Moved Dimmer from F7 to F11
2. Moved Brake from F11 to F7
8. Changed Brake Rate (CV117) from 0 to 127
9. Sound Settings
1. Exhaust Select - "Light 1"
2. Slip Rate Control - "Medium Slip Rate"
3. Dynamo Select - "Dynamo 1"
4. Whistle - "CN Flat Top 3-Chime" (though I'm still deciding...)
5. Bell - "Heavy Brass Medium Slow"
6. Injector - Lifting
7. Reverser - Johnson Bar
8. Airpump - Cross Compound
10. Saved the file to DecoderPRO.
11. Set the Dynamic Digital Exhaust (DDE)
1. Changed side rod clank high & low from 0 to 255
2. The factory settings had been:
1. CV2.503=60
2. CV2.504=150
3. CV2.512=32
3. Turned momentum off (set CV3 & CV4 both to "0")
4. Warmed up the engine by running it 2 minutes in each direction
5. Did the DDE calibration (see Steam User's Guide p. 22)
6. New settings changed to:
1. CV2.503=46
2. CV2.504=253
3. CV2.512=65
12. Finally set the chuff rate (CV114) per the process outlined in this video.
1. For this particular engine, it looks like a value of "67" matches better than the default/factory value of "57"
13. Reset the momentum
1. CV3=150, CV4=255
14. Saved the file to DecoderPRO.

A big part of my process for clearing the fog inherent in any new endeavor is to go DEEP into the rabbit hole . . . heh - I think I can call this case "Mission Accomplished." I still want to fiddle a bit with CV114 to see if I can get the chuff synch even better, but the main thing now is to actually put the #359 back into service and make sure it runs, acts, and sounds like I want it to.

'Cuz if it doesn't, I'll be going back to the workbench with it. And after over 10 months, I'd really like to avoid that!

If any of you out there have experience programming Tsunami2 steam decoders, I really hope you'll weigh in tips & tricks in the comments - or contact me directly by email. I'd love to know what you would have done differently - and if you have any advice/suggestions for anything else I should be sure to do.

Meanwhile, I'll untie myself from the proverbial railroad track, dust myself off, clean off the programming bench, and get to work on something else - maybe even the layout!