Number of DCS Engines on the Track and Active in the App

How many engines do you have on your track? How many are receiving power (example siding turned off, track turned off)?

Again, 2 things have to be true- the engine must have power, and DCS signal- to even respond to a command if sent- to remain on the active list.

Here's my honest impression. OK, so like me, you have a nice large collection of engines- all added to your app at some point in time. I really honestly struggle with the entire point of active VS inactive list in the first place as a feature- but that could be a discussion in and of itself.

It's literally this simple- DCS is 2 way communications, so if you send a command to a specific ID engine, it must respond back and through the TIU all the way back to the app. Now imagine you send a read command- that is trying to see all engines on the track and then everyone that responds back in the time period- stays active, and the ones that didn't respond or responded late, or the message from all the other traffic garbled it- well invalid response to they get moved to inactive.

So again, if say you ONLY sent commands during a running session to engines on the track that were already in the remote- the active VS inactive list should not change or update. OK maybe, it might add an engine to active if it was previously inactive, but not move other "active" engines- that you did not mess with to inactive.

However, say during a running session, you have a new engine- or you use the add MTH engine function- now again, you just scanned the track for all engine IDs and now you might possibly update the active to inactive list.

Again, a few things:

I think you are getting hung up about the active and inactive list- because to be fair it is somewhat confusing. In fact, I wish it could just be disabled or turned off as a function.

I think to expect all your engines, to always stay in the active list- that's just not how the system works in my experience under normal usage. Due to reads and other technical complications that may scan the track and then expect all engines to respond- let alone the traffic of all engines responding at the same time, and that assumes they all are on the track and have power and good DCS signal at that moment- just not realistic.

I think that due to the extra layer of commands needing to go through the WIU or wireless, let alone networking in general, then to a tablet, the OS, and then to the app on the tablet as another layer- I'm just trying to state the additional difference between say DCS remote control and the DCS app over Wifi. It is another layer and things can go wrong.

@SD60M posted:

I might have 20 active engines in the pad I am using one time...turn off the layout...come back the next time and only be able to "find" 4 engines.

Again, as an example, our club has 1 TIU, so 4 active tracks. In theory, if I had the turntable connected, those whisker tracks, another yard- technically they all would currently be load on 1 channel. Honestly, I do not think I could power 20 engines at the same time, on one TIU, using all 4 channels and have good signal to everything guaranteed. That's 5 engines per TIU track channel.

So absolutely, if I did one read just by accidentally swiping down at the top of the screen when choosing an engine in the app (remember swipe is a read/"refresh" command)- then absolutely- only the engines on the track that had track power and good signal to the TIU, and then further responded as expected- would remain on the active list. Again, refresh can either be helpful sometimes- or inadvertently kick many engines to inactive in other cases.

https://mthtrains.com/sites/de...ction/20as13831i.pdf

Thanks for the response.  I hope I am not irking you too much with these questions and situations.

How does one explain...two engines on the same track...I turn on that track...App sees nothing...I do one of those swipes...it refreshes and finds one of the engines...that engine starts right up.

Why did it miss the other engine?

Sometimes I get a list of engines...just their addresses...no descriptions...nothing.  What is causing that?  I thought maybe sub-standard tablet...but, I tried again with an iPad...same result.

After this, I will go away and ask no more.

@SD60M posted:

Thanks for the response.  I hope I am not irking you too much with these questions and situations.

How does one explain...two engines on the same track...I turn on that track...App sees nothing...I do one of those swipes...it refreshes and finds one of the engines...that engine starts right up.

Why did it miss the other engine?- Could be any number of reasons- the point is, a read is sent out, all engines then respond. Basic walkie talkie 101- only one device can talk on a net at a given exact moment- so 2 engines, both trying to respond- absolutely one could talk over the other one or be delayed or some other thing where the tiny response back all the way to the app was not met in time. Again, DCS is a 2 way signal, and we can run multiple engines at a time- but sometimes- in the overall protocol- there are instances where a timeout or "contention" can occur. Bottom line, the app got one good response, and the other response was either "talked over", garbled, or late within the timeout.

Sometimes I get a list of engines...just their addresses...no descriptions...nothing.  What is causing that?  I thought maybe sub-standard tablet...but, I tried again with an iPad...same result.

I think you are talking about adding engines function. Again, DCS is a 2 way protocol, the engine stores the name, road number, and other details, and when you add engine, the remote or app is trying to then add that to the database ID slot for that engine. There are 2 main ways this can fail. One is just a glitch in signalling. Maybe signal strength is low to that engine in that spot on the track, maybe some other engine or something was sending DCS signals and there was contention, maybe it was just timing and it timed out. Bottom line- the requested information was either not valid or late or garbled and it just adds a blank generic ID in the database ID slot.

Another way this can happen- upgrade kits. The PS2 and PS3 upgrade kits have special firmware, and as such, it lets you rename the engine using either the app or the remote. Unlike factory OEM firmware, the rename function again in an upgrade kit only- stores the new edited name and road number in the engine. (Edit background- when you rename in a normal PS2 or PS3 engine, that's an overlay displayed name in the remote or app- the engine name data in the engine is not modified). However, if you do a reset to factory defaults on an engine with an upgrade kit (again, PS2 or PS3 upgrade kit board) then it reverts to a blank name and road number. Only authorized techs with access to Dealer loader version of the MTH software can flash a serial number name file to an engine and make that permanent. Again, this is a scenario specific to engines with upgrade kits and original upgrade kit firmware/chain files.

After this, I will go away and ask no more.

You are not asking invalid questions- it's more just some of the limitations of DCS exposing themselves.

More so, I have some background in microcontrollers and electronics, some idea of basic handshake communications, I tend to dig into the "how things actually work" side of this down at the electronics level. The manuals and instructions simply do not go down to this level, and being honest, really are barely adequate. So it's understandable to me that someone might not understand why things happen in DCS, and there are even some aspects that even if you know why it happens, you might think that's not the best way for it to work.

I in no way, claim to know everything about DCS and someone might argue I get it wrong on occasion. I'm only going off of years of experience, the technical information I have access to, and details and topics posted in forums.

Thanks again.

Vernon is correct in everything I see above.  You just have to learn all the nuances so you don't drive yourself nuts when you're just trying to have fun.  DCS is just like that quirky friend you have to figure out.

The active/inactive list is another of those quirky features of DCS.  If you step back and look at it you can understand why is was done.  DCS does not have a way to select an engine by keying in a number, instead you select it from a list.  If you have 40 engines but only 2 are on the track, it would be a royal pain to scroll through a list to pick them out, whether on the remote or the app.

As Vernon explained, there are a number of ways to work with this “feature” so it is less annoying.

Don't forget the remote operating mode setting.  You can set it at NORMAL or SPEED.  If you set it at SPEED, it doesn't typically look for a response from the engine, just assumes it got the word.  This will help.  Also, if you don't want your engines being dumped into the INACTIVE list, DON'T use the READ button!  If you hit READ, anything that can't be found is moved to the INACTIVE list.  During normal operations, there's no reason to use the READ button, I haven't used it in months.

@gunrunnerjohn posted:

Don't forget the remote operating mode setting.  You can set it at NORMAL or SPEED.  If you set it at SPEED, it doesn't typically look for a response from the engine, just assumes it got the word.  This will help.  Also, if you don't want your engines being dumped into the INACTIVE list, DON'T use the READ button!  If you hit READ, anything that can't be found is moved to the INACTIVE list.  During normal operations, there's no reason to use the READ button, I haven't used it in months.

I think the OP was referring to using the app.

I have to say the gentleman that responded back to the original person that posted this are awesome and have a ton of knowledge. They all have helped me out so so much!!!

Hi all,

A little aside about the Active/Inactive list.  The only DCS feature that actually requires the Active vs. Inactive distinction is the ALL Engines function.  "All engines" has to filter for all engines that are actually on powered track.  The only other feature that effects the Active vs Inactive list is Lash-ups, but even that isn't actually necessary.

Personally, I RARELY use the "all engines" feature and I advocated getting rid of the feature when we were developing the app.  We could have eliminated the Active vs Inactive list entirely.  However, some of the guys at MTH R&D use "all engines" all the time and really wanted it in the app, so it stayed.

When you have too many engines on powered rails, they seem to soak up the signal. I forget the exact number per channel. I would bet the length of track together with the number of engines matters. Maybe wire size too. Try using more tiu channels on the layout. Also try removing stuff that soaks the signal like tmcc stuff without chokes installed.

I remember having too many engines powered got other things happening like start-ups as soon as power is applied (in command mode). I created blocks so that my engine yard tracks are switched off unless needed. I need GRJ's watchdog units but they're down the long list of stuff needed.

@Dave Hikel posted:

Hi all,

A little aside about the Active/Inactive list.  The only DCS feature that actually requires the Active vs. Inactive distinction is the ALL Engines function.  "All engines" has to filter for all engines that are actually on powered track.  The only other feature that effects the Active vs Inactive list is Lash-ups, but even that isn't actually necessary.

Personally, I RARELY use the "all engines" feature and I advocated getting rid of the feature when we were developing the app.  We could have eliminated the Active vs Inactive list entirely.  However, some of the guys at MTH R&D use "all engines" all the time and really wanted it in the app, so it stayed.

I'm glad they kept the "All Engines" feature. I do use it on some layouts when I have multiple consists chasing each other and everything needs to start at the same time and at the same speed.

I've found results similar to Joe's experience. When there were a lot of engines running on the layout under DCS at Angels Gate, we sometimes had problems finding/activating engines. The BIG advantage of the handheld remote is that you can tether it to TIU to add it to your remote without risking hijacking an engine on the layout.

One word that stands out in all the replies I read is "nuance" (not to be confused with "nuisance"...LOL). I have had similar experiences to those of SD60M, and various times. Can't explain them and don't feel I should try given the significant information put forth here above by Others.

My comment here is to pass on something I learned on this forum "the hard way", and that is having a number of DCS engines on your "active " list when you're only running a couple means that, if truly "active-ready", they are powered enough to run the chronology....whether you are using them or not! To wit: I have newer engines that may have  only18 scale miles on them but 100 hours on the clock!!  Bad karma!

I'd argue it's not as bad as idling your car in the driveway in case you want to go somewhere, but it seems somewhat akin to that in terms of keeping the electronics "hot" because you're able to. Remember: I did that out of ignorance! I have had to force myself to be diligent and remove engines that are on a powered track siting there just  because they look cool. I will be rebuilding my layout this winter and will definitely include a means to switch the power off under whatever may be present "for looks".

For what it's worth, I only use iPads. Can't speak for the DCS remote.