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Discussion Starter · #1 ·
A lot was made by LGB over recent years regarding the need for "P" (parallel) products. My LGB Central Stations 2 & 3, LGB Remotes, LGB Transmitters and one LGB Receiver have the "P" upgrade but another LGB Transmitter and Receiver do not. Since the LGB Central Station 1's are Serial only I might as well keep a Serial receiver for use with them (and for use with a LGB Analog Throttle). Strangely this Receiver will apparently work in Parallel but only with specific Transmitters.

I have six questions:

1. I would presume that all decoders sold by all manufacturers today have parallel capability. Is that correct?

2. How do I (you) know if older decoders perhaps including old production LGB 55020/21's are serial or parallel?

3. Is Parallel or Serial capability a factor at all when a LGB Universal or Loco Remote is TETHERED to a "P" rated LGB Central Station? In other words is Parallel and Serial strictly a radio control function?

4. Would an LGB ANALOG throttle be affected by whether a TETHERED LGB Universal or Loco Remote was Parallel or Serial capable?

5. Would an LGB ANALOG throttle be affected by whether a LGB Universal or Loco Remote WITH Transmitter and Receiver was Parallel or Serial capable?

LGB said:

"To take advantage of parallel function commands, you need an MTS Central Station "Type 2" (LGB 55005) with upgraded software that includes "p" capabilities or "Type III" (LGB 55006).

In addition, any input device and wireless component used to transmit the "parallel" commands to the Central Station must have "p" software. These include:
55015 Universal Remote
55016 Loco Remote
55050 Wireless Transmitter
55051 Wireless Transmitter, USA
55055 Wireless Receiver
55056 Wireless Receiver, USA
55060 MTS Computer Interface"

6. Since the LGB 51070 Analog throttle is not listed above and the 51070 instructions do not make any reference to "P" rated accessories I assume this means the the "P" upgrade has no effect on analog operations. Is this correct?

Thanks,

Jerry


Note: I am not planning (or looking for advice) on buying anything beyond some cheap decoders. I am simply trying to better understand the capabilities and limitations of what I already have so I can get the best performance from what I already own.
 

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Jerry,

As near as I can tell, only the LGB 55027 is parallel capable. 55021's are all serial only unless they are converted (and I am not sure they can be). Some of the decoder equipped locos are supposed to be parallel capable but the only one I have is the undecorated mogul and that is serial only. The main issue is the LGB digital sound systems, none of which are reported to be parallel capable. The Phoenix Sound Systems P5 works fine on parallel and it is nice to have the instantaneous response to pushing a function button. This is gleaned from a conversation with Klaus Stork at Massoth USA who was very helpful. The good thing from my perspective is that everything I have tried so far with the Massoth central station is capable of 28 speed steps with makes for much smoother operation.

Hope this helps,
Keith
 

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Hi Keith-

Your LGB #23191 should be able to understand parallel and serial commands. When you set up the #23191 in the Navigator, did you select parallel commands?

Best regards,
Bob
 

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Hi Keith-

A few additional notes:
-55021 decoders (from V2.8+) are serial/parallel. Older decoder versions must be upgraded or replaced with Massoth decoders to generate the rapid F1 pulse chain needed with “P-upgraded” sound boards from “decoder interface” and “direct decoder interface” locos.
-LGB 6500x series sound modules are serial/parallel
-All onboard decoders are serial/parallel.
-All sound locos with onboard decoders understand serial/parallel commands.
-Early 55021 decoders and 6500x sound modules cannot understand 128 speed step commands. All versions of these products understand 14/28 speed steps.

If you are curious, here is some additional information.
http://groups.yahoo.com/group/gscalegroup/message/27973

Best regards,
Bob
 

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Hi Jerry-





1. I would presume that all decoders sold by all manufacturers today have parallel capability. Is that correct?






All NMRA decoders for largescale are parallel. Some decoders can understand both serial and parallel.






2. How do I (you) know if older decoders perhaps including old production LGB 55020/21's are serial or parallel?





Read the decoder version in CV#7. There are other visual clues given on the Reutimann website, but I suggest reading the decoder version number.






3. Is Parallel or Serial capability a factor at all when a LGB Universal or Loco Remote is TETHERED to a "P" rated LGB Central Station? In other words is Parallel and Serial strictly a radio control function?





No. There are other performance enhancements.

1. Moving between two locos is much easier. The “hand-off” function is no longer necessary.

2. Short circuit timing was fixed on the central station. This improves reversing loop module operation.

3. Wireless range is enhanced.

4. Upgraded devices can transmit serial and parallel commands.






4. Would an LGB ANALOG throttle be affected by whether a TETHERED LGB Universal or Loco Remote was Parallel or Serial capable?





No.






5. Would an LGB ANALOG throttle be affected by whether a LGB Universal or Loco Remote WITH Transmitter and Receiver was Parallel or Serial capable?





Yes. The Universal/Loco Remote wireless range increases with the P upgrade.







6. Since the LGB 51070 Analog throttle is not listed above and the 51070 instructions do not make any reference to "P" rated accessories I assume this means the the "P" upgrade has no effect on analog operations. Is this correct?






The “P upgrade” has nothing to do with the 51070 analog throttle.



Best regards,

Bob
 

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Discussion Starter · #11 ·
UPDATE AND CORRECTION:

My "serial" operations of the Digitrax and MRC decoders only involves the motor output of those decoders.

Based on subsequent posts it is apparently correct that these decoders ARE NOT capable of serial operations with the exception of the motor output.


I am happy to say that I have not run into any problems using the Digitrax DH123D, DG583S or MRC AD322 decoders when running their motor output to run locomotives with the LGB MTS Central Station 1 (Serial Only).

So far all decoders I have tried have been able to control the motor output both under Serial and Parallel operations.

Jerry
 

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Jerry-


I am happy to say that I have not run into any problems with the Digitrax DH123D, DG583S or MRC AD322 decoders when running them with the LGB MTS Central Station 1 (Serial Only).
So far all decoders I have tried have worked both under Serial and Parallel operations.
Jerry



Your statement is misleading.

Please correct me if I am wrong, but you are using the decoder's motor leads to power the loco circuit boards. You are not controlling lights, smoke, sounds, etc. from the decoder's F2-F8 function outputs.

Obviously, there would be no serial versus parallel function compatibility issues if you do not connect the decoder's F2-F8 outputs.

If you did connect lights/smoke/etc. to the F2-F8 function outputs of these decoders, you would not be able to trigger these function outputs with an MTS I or MTS II (serial) system.

Best regards,
Bob
 

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Discussion Starter · #13 ·
to mislead (third-person singular simple present misleads, present participle misleading, simple past and past participle misled)

To deceive by telling something that is not true.
To say something for purpose of causing the receiver to think or act in a certain way.
To lead astray.



Perhaps stating that my comments are misleading is in itself misleading.

Since my stated purpose for my inexpensive decoders is to use the decoder's motor leads to power the loco circuit board and that purpose seems to be served both in parallel or serial mode the result is that for me serial and parallel operations are functioning satisfactorily with the inexpensive decoders.

I make no pretense of being any sort of MTS/DCC expert and my comments reflect my experiences (nothing more and nothing less).

Suggesting that I am somehow misleading is to suggest that there is some intention on my part to provide inaccurate information.

If a serial command to a decoder results in a locomotive speeding up, slowing down or changing direction that suggests to me that the serial command is communicating with the decoder.

If someone else wishes to provide further clarification on other limits that may exist in the serial communications with a decoder they are welcome and encouraged to do so.

My comments may be less than comprehensive due to my limited knowledge of DCC operations but they are not misleading.

Rather than challenging my comments it would be much more helpful to everyone to provide detailed information regarding how serial operations might be possible to control motors but yet not be able to control F2-F8 functions. I don't think these decoders even have all the F2-F8 functions.

If I knew what to look for I might find time to check for further serial compatibilities (if anyone is concerned about it).

I am not selling or promoting anything. If there are limitations to the Digitrax and MRC decoders I would be the first to want to know (and to want others to know) about them.

Jerry




"Your statement is misleading.

Since you are using the decoder's motor leads to power the loco circuit board, you are not controlling lights, smoke, sounds, etc. from the decoder's F2-F8 function outputs.
Obviously, there would be no serial versus parallel function compatibility issues if you do not connect the decoder's F2-F8 outputs."
 

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Jerry-


to mislead (third-person singular simple present misleads, present participle misleading, simple past and past participle misled)

To deceive by telling something that is not true.
To say something for purpose of causing the receiver to think or act in a certain way.
To lead astray.

Perhaps stating that my comments are misleading is in itself misleading.
...
Suggesting that I am somehow misleading is to suggest that there is some intention on my part to provide inaccurate information.



You can lead someone astray without intent, so my original comments were correct.

By providing an incomplete description of your installation, your post gives readers the impression that NMRA function outputs F2-F8 can be controlled by an MTS serial pulse chain.


Rather than challenging my comments it would be much more helpful to everyone to provide detailed information regarding how serial operations might be possible to control motors but yet not be able to control F2-F8 functions.



Serial function commands have nothing to do with motor control. They affect DCC functions F2-F8.


If I knew what to look for I might find time to check for further serial compatibilities (if anyone is concerned about it).



Try controlling the F2-F8 function outputs of the referenced decoders with a serial MTS system. (To test, you can simply connect 24V bulbs between the appropriate function output and V+.) You will not be able to trigger these functions with a serial MTS system.

Best regards,
Bob
 

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Posted By rwbrashear on 09/02/2008 9:25 AM
Jerry-

I am happy to say that I have not run into any problems with the Digitrax DH123D, DG583S or MRC AD322 decoders when running them with the LGB MTS Central Station 1 (Serial Only).
So far all decoders I have tried have worked both under Serial and Parallel operations.
Jerry


Your statement is misleading.





To state that Digitrax or MRC DCC decoders support LGB serial operation is not misleading, you're too kind with that statement, it's dead wrong!

Neither Digitrax not MRC have ever supported LGB serial operation and they will also never support LGB serial operation in the future.

If you need LGB serial operation, there are a handful of European decoder manufacturers who support this LGB proprietary serial pulse chain concept, and even there it can vary from decoder type to decoder type.

Knut
 

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Discussion Starter · #16 ·
I would much rather be dead wrong than misleading.

Considering the fact that most of the used LGB MTS products that are being sold on eBay tend to not have the "P" (parallel) upgrade it is amazing (to me) that there are no clear cut statements by decoder manufacturers in their specifications about support or non-support of serial operations.

Sometimes it takes an inaccurate comment to bring out the full facts about something.

At least now someone (Knut) has finally stated clearly that Digitrax and MRC decoders are NOT capable of serial operations.

Some people might suggest that serial is a LGB only consideration but as far as I know LGB is the ONLY large scale manufacturer to have adopted a policy of factory installations of decoders.

In my opinion to try to ignore LGB serial operations is like trying to ignore an elephant sitting in your front yard.

In my case it appears that for whatever reasons (that I do not understand) I will still be able to continue my installations of the MRC AD322 and Digitrax decoders in my locos since I am only using the motor output of the decoders which apparently are capable of controlling the motor output of those decoders via serial commands.

Cheers,

Jerry
 

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Discussion Starter · #17 ·
This brings up the question of other manufacturers such as QSI.

Can anyone say whether the QSI sound decoders are capable of LGB MTS serial operations when plugged into the Aristo-Craft DCC socket?

For that matter which manufacturers other than Massoth are capable of serial operations?

Thanks,

Jerry



Posted By krs on 09/02/2008 6:01 PM
If you need LGB serial operation, there are a handful of European decoder manufacturers who support this LGB proprietary serial pulse chain concept, and even there it can vary from decoder type to decoder type.
Knut
 

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Jerry -
I get the feeling that you may not understand exactly what "serial" operation means.
Not surprising - I never liked the terms serial operation and parallel operation that were coined by LGB.
A few of sentences on history: When LGB initially brought out MTS (which was quite similar to DCC but not identical), one of their early throttles was an MTS mouse. It was really geared for very easy operation for kids, after all we are talking about Toy Trains here, and that mouse had a button that would activate a function on the loco.
Didn't take long and just activating one function on a loco was not enough, people wanted to blow the horn, turn on the bell, and activate more than one function.
With DCC, the NMRA standard allowed for that by assigning different coded 'packets' (the electrical control signals embedded in the DCC signal on the track) for each function output. So when you pushed function button 1, the central station would send the appropriate 'packet' signal for F1, the decoder would detect it and turn on the F1 output of the decoder, same for F1 to F8 and later for higher function outputs. Each function outputs had a different 'packet' signal that was generated by the central station based on which function button was pushed.
Well, on the MTS mouse there was only ONE function button, so how do you control functions 2 and functions 3 and 4 etc.?
Instead of stating the obvious - if you only have one function button you can only control one function, LGB decided to come up with the serial pulse chain idea where you just push that function button multiple times to activate the higher function outputs.
So if you want to send function 3 for instance, you push the function button on the mouse three times. the MTS centarl station sends out the 'packet' for F1 three times, the MTS decoder counts the number of F1 packets it receives and in this case turns on the F3 output. Note that the MTS/DCC signal on the track is still fully NMRA compliant, but any decoder that cannot be programmed for this serial pulse chain operation will recognize that signal as three F1 signals not as one F3 signal.
With only F2 and F3 to activate this way, that process worked reasonably well, but it not only became cumbersome with the higher functions, say F7 where you had to push the mouse button seven times, but it also became unreliable. If noise on the track for instance distorted one of these F1 packets sufficiently, the decoder would not detect it and would trigger an F6 output for instance instaed of F7, Then there was also the delay while all these pulses were being sent and of course the functional incompatibility with DCC.
So LGB eventually introduced what they call "parallel" operation which is simply the normal DCC operation, each function has its own unique DCC packet and the function is activated as soon as the packet signal is received.
So..........any DCC decoder will work fine with any MTS system (as far as this capability is concerned, there may be other incompatibilities) as long as you have no need to operate functions 2 and up.
Jerry - to answer your last question, I think it's safe to say that only European Manufacturers are compatible with LGB serial operation and then only a few of them. I don't think any US manyfacturer ever implemented this either on the decoder end or the Central Station end. A while back, someone made a converter that would accept serial pulse chain at the input and output the proper DCC signal (called parallel by LGB), but since that still left you with the inherent unreliability and delay of function activation, I doubt it's still being sold.
Zimo for one has a decoder that provides serial pulse chain operation at the output of their decoder to drive an LGB sound system that requires serial pulse chain.
And - just to confuse things a bit more (maybe you should not read this) - the standard DCC signal which LGB calls parallel is actually a string of serial pulses that make up the packet - they are just sent so fast that it seems like one signal and the SUSI interface and the latest LGB sound interface from decoder to sound unit is also serial - but also very fast.
 

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Discussion Starter · #19 ·
Hello Knut,

Actually I do understand what you said and I did understand the serial (multi-pulses) vs parallel (fast pulse) operation.

What confuses me and had caused my misinterpretation of "serial compatibility" was/is the issue of motor control.

When I run MTS/DCC I get the "steps" of speed increases which to me seemed to fit in with the serial pulse concept (more pulses = more speed). Actually this is one reason I have preferred tethered analog operations (no steps).

If motor control is not an "F" function then what is it?

How is it possible that a motor function can work with a serial controller when the F functions cannot? If serial cannot talk to the functions how is it able to talk to the motor?

For my primary operations with MTS/DCC I use and will continue to buy and to use the more expensive LGB/Massoth (and perhaps Zimo) decoders but with my multiple layouts (especially my portable trailer layout) I prefer to continue to use the LGB Central Station 1's because of their low cost ($50). They will be used with low cost locos (Lionel, LGB Starter Sets etc.) and for that layout and those locos I am unwilling to spend $80+ for a decoder.

The end result is that while I have converted my primary layouts to MTS "P" capability I still want to maintain serial capability whenever possible. At least I know that LGB's MTS Central Stations are backwards compatible with serial decoders. I would not be willing to consider a higher level DCC system that might not recognize some of my old decoder equipped locos.

The more I learn about DCC the more incompatibilities I seem to run into. It seems one almost has to become an expert in order to build a compatible system.

I thought I could talk to some local HO DCC guys but they did not know much about what I was asking.

At least I am making progress and I am ending up with more MTS/DCC capable trains than would have been possible without these inexpensive decoders.

Thanks,

Jerry
 

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Hi Knut-

Good explanation.

You wrote:
And - just to confuse things a bit more (maybe you should not read this) - the standard DCC signal which LGB calls parallel is actually a string of serial pulses that make up the packet - they are just sent so fast that it seems like one signal and the SUSI interface and the latest LGB sound interface from decoder to sound unit is also serial - but also very fast.


Just to clarify, with a "P" upgraded LGB system, the commands through the rails are NMRA parallel commands. The commands between a "P-enabled" 55021 and a "P-upgraded" loco circuit board are high speed serial pulse chain.

Onboard decoders communicate with factory installed sound/accessory modules through a proprietary high speed, 4-pin interface. As a side note, there are several decoders which have the ability to produce this same signal, allowing users to replace/upgrade LGB onboard decoders.

Best regards,
Bob
 
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