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Switching DCC Systems

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Posted by rrinker on Monday, August 2, 2010 9:00 PM

 The only one you can turn off is the purge beeping, it will still beep on power up and on a short, or other error.

                                      --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Hamltnblue on Monday, August 2, 2010 8:52 PM

I'll leave them on for now while I get used to it.  It did come in handy while testing sections with for shorts with the quarter trick.  Actually I used the back of the NMRA track gauge.

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Posted by rrinker on Monday, August 2, 2010 8:49 PM

 Yup. You can turn the beeps off it it's annoying. By myself in my room, it's loud. When we have the modular layout on display in a public location you'd never hear it.

                                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Hamltnblue on Monday, August 2, 2010 8:39 PM

Thanks for the info.

Getting lots of reading in the last few days.

I actually ran across the purge function.  I was reading the manual some with a couple of loco's idling and the DCS100 beeped 3 times.  I thought it was an error code and looked it up.  Apparently the system purged one of the loco's I had been using earlier.

Springfield PA

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Posted by rrinker on Monday, August 2, 2010 7:17 PM

 I don't know if it's on his site, but on the DIgitrax group on Yahoo, Don Crano gave about the most detailed and comprehensive overview of what all that means and just how the Digitrax loco 'slots' work that I've ever seen. I don;t think anyone pulled it out and made a file of it, but you can check the files section there as well as Don's site. Failing that, you can search the message archives for his message.

 Dispatching does release the loco for another throttle to pick it up, but a loco at speed step 0 with no commands sent to it for the timeout period (choice of two by setting OpSw 13 - either 200 seconds (default) or 600 seconds) will be purged, if not in consist. A consist will not be purged unless it is first broken up. There's actually an intermediate state but the bottom line is that if you always stop a loco when done with it and dispatch it, you will never see the Slot=full error indicating there is no room for the command station to handle any more locos.

 Oh yeah - out of the box the DCS100 is defaulted to 22 slots, you have to change OpSw 44 to allow for 120 slots. But unless you really need to run that many locos simultaneously, don't do it, the system will perform faster if it only has to scan 22 slots. In JMRI there is a Loconet Slot Monitor utility that will display the status of all the slots, including the system reserved ones that are used for dispatching, the program track, the fast clock, and configuration info. Don't worry, it's 120 total slots PLUS the system ones. By looking at the slot monitor once you have a PR3 or other interface and reading Don Crano's wrtiteup, you'll have a pretty good understanding of what's going on inside. Oh yeah, using the slot monitor you can see that there are only functions F0-F8 managed internally - liek I mentioned early, F9+ are handled by the throttles since the system is peer to peer. That's why I can plug my DT402 into my Zephyr (Zephyr only does up to F8 on the console) and get F0-F28.

 Edit: Here's an item from the Digitrax Tech Support Depot that somewhat explains the slot states: http://tsd.digitrax.com/index.php?a=1444  It's for a DB150 but the DCS50 and DCS100 work the same, just with different numbers of slots. There's a bunch of good info int he Tech Support Depot, not all of it is simply copied from the manuals.

                                                 --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Hamltnblue on Monday, August 2, 2010 6:08 PM

Thanks  I'll give it a try.

As far as the dispatch is concerned, what exactly does it do?  Free the loco or consist up for someone else to pick up?

If so how do you clear the loco buffer? I though I read that it should be cleared now and then to prevent it from filling up.

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Posted by mfm37 on Monday, August 2, 2010 5:25 PM

Hamltnblue
.

Is there a way to run 2 consists on the 402 throttle?

 

 

Yes.

 Build you first consist. When done, make the right throttle active. Press "LOCO' then press "Disp" . The top consist address is now "dispatched" to the system and any throttle can acquire it including the DT402's left throttle.

Now build your second consist with the DT402. When done, the top address for the second consist will be controlled by the right throttle.

Now make the left throttle active, press "LOCO". Select the top address of the first consist the press "LOCO" again. The top address of the first address will now be controlled by the left throttle.

  If you want to go even further. Let's say that first consist is a pair of helpers and you want to cut it into the train being pulled by the second consist. Just press "MU" then + and the first consist will be consisted to the second consist. All locos will now be controlled by the right hand throttle.

To remove the helpers, press "MU" then - .  The helper consist will be removed from the right throttle and be back in control on the left throttle.

 Martin Myers

 

 

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Posted by rrinker on Monday, August 2, 2010 7:58 AM

 Two things to remember which will probably be the keys. First, the 'top' address of the consist does NOT have to be a real loco address. You cna have train 1 as a consist which has locos 2111 and 2113 on point. Of course, the top address has to be one that doesn't exist - if you make consist 1 with locos 2111 and 2113, and you happen to have old 1-spot sitting alongside the roundhouse, it's goign to move along with the consist. But the point is, the controlling address of the consist does NOT have to be the address of any loco in said consist.

 Point 2, dispatching a consist does NOT break it up. This has caught people unawares when they select a loco and when they start to move it, another one on the opposite side of the layout starts moving as well. Oh yeah, they used to be consisted. So you can dispatch a consist and later aquire it on another throttle and all the assigned locos will run. In fact this is the only way to get a consist on the UT4, the UT throttles do not have the capability to create or break up consists, but you can create one on a DT throttle and hand it off to the road engineer who has a UT throttle.

                                            --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Hamltnblue on Sunday, August 1, 2010 8:53 PM

Thanks,  I think I'm still a bit too much of a Digitrax newb to keep up with that post LOL .

 

Springfield PA

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Posted by jalajoie on Sunday, August 1, 2010 8:20 PM

Hamltnblue

Is there a way to run 2 consists on the 402 throttle?

A few years ago, for a test I did run 2 Universal consists on a DT400R throttle. I first built a Universal consist in the usual manner, dispatched it, acquired it and run it on the left knob. After that another Universal consist was built and controlled with the right knob. This was the only time I did it there is probably other ways to do this. I am thinking maybe building an Advance consist to be run on the left knob and a Universal or another Advance consist on the right knob. 

Jack W.

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Posted by Phoebe Vet on Sunday, August 1, 2010 8:19 PM

Sure.  Once you build the consist the system treats it like a single loco.  Any throttle can then run the consist.  Just select the prebuilt consist and run it.

Dave

Lackawanna Route of the Phoebe Snow

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Posted by Hamltnblue on Sunday, August 1, 2010 7:43 PM

It seems they have it figured out and have been able to add new product without too much problem.  I did the switch over to the Digitrax today and ran for a couple of hours testing fresh laid track on the section I'm re-building.  The 402 controller is growing on me. It's nice to be able to run 2 loco's at a time without any switching. I was actually running a consist of SD70's  and  a switcher.

Is there a way to run 2 consists on the 402 throttle?

Springfield PA

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Posted by rrinker on Sunday, August 1, 2010 7:08 PM

 A good example of the peer to peer approach is, the code in the command station PIC doesn't even handle functions above F8. The throttles handle the higher functions by telling the command station to send the NMRA DCC packet corresponding to the appropriate function. This is also why that evn before the DT402 came out, you could access F0-F29 on a Digitrax system using the computer throttles in JMRI. There has only been one real update to the firmware in the DCS100, and that was because the earliest versions, back when 8 functions was a lot, didn't handle anything higher than that. There was an update many moons ago that 'fixed' it so it could handle the then-new 12 function throttles. No additional update was required to add the new 29 function throttles, just plug in and go.

 The menus themselves are also not generated int he command station, the throttle firmware handles all that They did finally get smart with the DT402 in that the firmware is now user-updateable, in case they need to change something, but there hadn't been any updates for the DT400. As for the extra ROM and RAM in the PH-Pro, I don;t think that particular Z80-based controller has much on-board, so external was needed. I beleive the external RAM chip on the DCS100 is to store the settings, backed up with the coin battery, although it MIGHT store loco and consist info since you can reset all that stuff by pullign the battery for a few minutes. Actually, it probably does because the 16F74 only has 192 words of internal RAM. 4K of program space. A simple switch to a 16F77 would give 8K of program space. Probably the reason they haven't yet made a command station that can handle more than 120 locos is the speed of interfacing the external RAM. If the code has to go throut that RAM to keep loco info refreshed and the access is serial insteadof parallal, it can take an awfully long time to process a loop. I guess the alternative would be a PIC with much more on-board RAM, or some alternative interface. Also, I guess it was a cost decision to skip the interfaqce - the 16F74 has a UART so a serial port could be added fairly trivially - probably no code space though, plus then you'd be stuck with an RS-232 interface which is pretty rare on computers these days. The 16F873 used in the Hans DeLoof Locobuffer itself has 4K of program space, although the code isn't nearly that big.

                                              --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Stevert on Sunday, August 1, 2010 6:39 PM

Hamltnblue

Good Points.  Maybe the intention is for the base unit to act as a traffic cop more than a central processor, with the smarts in the controllers and items like the PR3

 

  Since the LocoNet is an actual peer to peer network, as Randy mentioned, the command station isn't really a traffic cop so much as it is another one of the "smart" components.  

  You can actually set up a stand-alone LocoNet without a command station.  I do that all the time with my PR3, for example when I'm programming a DS64, or when it's first installed on the layout and I don't want to power up the whole layout to test it.

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Posted by Hamltnblue on Sunday, August 1, 2010 4:58 PM

Good Points.  Maybe the intention is for the base unit to act as a traffic cop more than a central processor, with the smarts in the controllers and items like the PR3

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Posted by cudaken on Sunday, August 1, 2010 4:57 PM

  When I first got my PR 3, it would not read any sound decoders. Luckily Simon 1966 came over again! Big Smile He ran my PR 3 at his house and had no issues. Seems not all USB ports have the same power output? He switched the USB port and did some changes in the Comfig and I was fine. My computer is pretty old, from around 2004 so a newer one may not have the problem I did.

 Ones you have one, you will never look back. All so the reason I did not go with the Super Chief! 

                     Ken

I hate Rust

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Posted by rrinker on Sunday, August 1, 2010 4:42 PM

 However using an external deivce to connect to Loconet gives some HUGE advantages to the Digitrax side. A computer program like JMRI can 'see' whatever anyoen does with any throttle on the Digitrax system - you can't do that with NCE. Say you have a dispatcher panel with turnout controla nd someone issues a command from their handheld to throw the switch. With NCE, the only way you can possibly 'see' this is if you hook up a contact on the switch machine to a feedback device. With Loconet - as soon as you hit the key on the throttle, the panel will change to reflect the change, no feedback devices needed. Everythign that happens on the network can be seen and acted upon - Loconet is peer to peer not polled so the Locobuffer or PR3 can see the traffic between any devices on the network, such as an occupancy detector sending a command to a signal controller. Or intercept and act upon the commands.

 This was how I plan to provide for both dispather and solo operation with a loco control option for dispatcher controlelr turnouts. The local panels will input via LocoIO boards, which generate loconet messages in response to an input trigger, or can turn outpus on and off based on loconet messages. Pushing a button will send a command to say throw turnout 10 to reverse. If in dispatcher mode, the panel code in JMRI will 'see' the command to switch turnout 10, but will only act on it if the dispatcher has enabled locao control by using the built-in logic (no programming required) which basically would state IF turnout10 Reverse and Turnout10 Local Control On, then turnout 1000 Reverse where the DCC decoder connected to the turnout would have an address of 1000. Manual mode for operating solo or without a dispatcher would simply link the button that generates the turnout 10 reverse message to turnout 1000 without the extra check for the local power. And by using stationary decoder addresses above 1000 , or enabling the 'Bushby Bit" on the command station, no operator can 'cheat' and change the turnout position.

 Thre more, a LOT more. You can also have multiple interfaces connected to Loconet - some larger layouts do this where they break up the dispatcher job into two, say one for each division represented on the railroad. Two or more computers connected to the Loconet, each controlling its part of the railroad.

                         --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Hamltnblue on Sunday, August 1, 2010 3:53 PM

While switching the Digitrax over to the layout I decided to open up both the NCE and Digitrax to see how their architecture compared.

Both systems utilize 8 bit processors and are up to date with surface mount devices.

The Digitrax uses a Pic processor (PIC 16F74) and has an LH5164AN-80L off board ram. No external Rom was seen.

The PHPro uses  a Z80 family chip (Z84C008VSG) and has 256k of ram( CY62256NLL) and a 256k eprom chip.  The extra rom/ram is probably for the menu structure.  There is also a Z84c9008VSG I/O controller on-board (For the RS-232 interface)

This is probably why digitrax uses cryptic menu's. It has to. I'm sure it's also why they have to have products like the PR3 for computer interface.

 

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Posted by Hamltnblue on Sunday, August 1, 2010 12:21 PM

Thanks for the info. I'll be ordering one shortly Smile

I agree that a booster shouldn't be used on a program track for new installs but for manysound loco's I don't see another way to read current CV settings.

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Posted by rrinker on Sunday, August 1, 2010 11:50 AM

 Yes, the PR3 has a standalone mode, It needs a power supply, and a USB cable to connect to your computer. And a couple of wires to apiece of track. I was goign to upload the pictures of my test/programmign track I took but none of them came out very well so I need to take more. I used a piece of that Rubbermaid laminated shelf wood, 3 Atlas rerailers, plus a 9" section of Atlas track cut in half. The track is all soldered together with the rerailers in the middle. I used CA to attach a pair of Kadee coupler guages to the ends (after cutting one rail at each end to insualte them - I used the old metal Kadee gauges). A pair of wires are sodlered to the rails, and I mounted my PR3 with double-sided tape to the board. I can use this for programming locos or testing cars - I still need to mark off NMRA weights at increments along the track so you cna just run a car to the end and read off how much it should weigh. And maybe get a second NMRA gauge and attach it with some steel wire to the board so it doesn't grow legs.

 The PR3 in standalone mode can program just about anything, plus program sounds into Digitrax sound decoders. I've actually not had any problems programming what few sound units I've worked on with just my Zephyr, and I didn't use the 'blast mode' or anything. That's pretty much limited to my Loksound equipped T-1, a Digitrax SoundBug, and one of the new QSI aftermarket decoders I installed in a Genesis diesel for someone. I really don't like these program track boosters as they defeat the purpose of a low-power program track ( so you can test your install before subjecting it to full track power, so if it's mis-wired it won't fry the decoder). Like the short-recovery inrush current problem, the programmability issues are a DESIGN DEFECT IN THE DECODER and not the shortcomings of the DCC system. They can trot out "applicable NMRA standards" all they want but the fact remains you CAN (and some have) build a decoder with a large keep-alive capacitor that does NOT cause a huge current inrush when power is applied and secondarily does not cause too great a load on the program track.

                                 --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Phoebe Vet on Sunday, August 1, 2010 11:37 AM

Hamltnblue

So the PR3 can be used without a system?

 

Yes, it can.

Dave

Lackawanna Route of the Phoebe Snow

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Posted by Hamltnblue on Sunday, August 1, 2010 11:20 AM

So the PR3 can be used without a system?

 

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Posted by mfm37 on Sunday, August 1, 2010 11:05 AM

 You would need a booster if using the PR3 in MS100 mode. Used that way, it is just an interface between the command station and the computer so readback would be dependant on the limits of the command station.

Using a PR3 as a stand alone programmer, there would be no need for a booster. It has plenty of power when used as a stand alone.

Martin Myers

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Posted by Hamltnblue on Sunday, August 1, 2010 11:04 AM

Sounds tempting for sure.  I'll have to step up the timeline for getting my wife a new laptop so I can have her current one. Whistling

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Posted by cudaken on Sunday, August 1, 2010 11:01 AM

Hamltnblue
Will the PR3 allow you to read CV's on sound loco's or is a program booster needed with the Digitrax?

 

 I had only one it would not read, it was a CSX Blue Line GE AC 6000. Odd thing is it would read the Blue Line UP GE AC 6000?

 On the sound page, you get a read out of all the individual sounds, like Chuff, Bell, Pop off etc and you can change them individually. No looking up the CV's, very handy.

               Ken 

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Posted by jalajoie on Sunday, August 1, 2010 10:02 AM

There is no need for a booster with a PR3.

Jack W.

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Posted by Hamltnblue on Sunday, August 1, 2010 9:14 AM

Will the PR3 allow you to read CV's on sound loco's or is a program booster needed with the Digitrax?

Springfield PA

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Posted by cudaken on Sunday, August 1, 2010 5:41 AM

 The DT throttle's is what sold me on Digitrax. Makes running two trains on the same line so easy.

 You got to try the PR 3, only time I use my SEB to change CV's is when I am speed matching.

                  Ken

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Posted by SpaceMouse on Saturday, July 31, 2010 11:17 PM

 I've used both a lot and like them both. I like the DT400 throttle better. My personal preference.

Chip

Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.

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