Multiple discharges from decoder

[PeterCook]

I am using Railmaster running on a laptop thru an Elite controller and I am delighted with the setup Occasionally When I switch points from the Railmaster the decoder sends out multiple discharges of power. I can here the points motor try to switch the

 

point multiple times. Everything is Hornby, points, points motor etc. When I use the Elite controller I don't get multiple discharges. Now my question is this is it normal and will it hurt the point motor.

[DCCTinker]

RailMaster does send out two pulses to the point motor, to ensure it has actually moved.

 

It's playing safe in case you might have a slightly sticky point and don't want to keep looking at it and re-firing it.

 

It shouldn't fire more than twice,

 

though. If it is firing "Multiples times" then you could have a dodgy connection between computer and Elite (USB cable or USB port).

 

[PeterCook]

Thanks. I think my USB cable I am using may be a bit dodgy as some times it wont connect laptop to Elite. Off to computer shop for a new cable.

Thanks

[Gregd99]

DCCTinker said:
RailMaster does send out two pulses to the point motor, to ensure it has actually moved.

It's playing safe in case you might have a slightly sticky point and don't want to keep looking at it and re-firing it.

That's

interesting to know. There is an undocumented feature of the xpressnet implementation in the elite where it forgets commands from the PC from time to time. Having the PC send two commands to the elite would also help to avoid this problem translating into

a problem on the layout.

[Fireman_Ian]

Gregd99 said:

DCCTinker said:
RailMaster does send out two pulses to the point motor, to ensure it has actually moved.

It's playing safe in case you might have a slightly sticky point and don't want to keep looking at it and re-firing

it.

That's interesting to know. There is an undocumented feature of the xpressnet implementation in the elite where it forgets commands from the PC from time to time. Having the PC send two commands to the elite would also help to avoid this problem

translating into a problem on the layout.

I have had this exact fault with my programs running in railmaster with locos not starting/ stopping when they should.
My solution was to double up each command line in the program sending each command

twice 0.1 sec apart. this completely solved the problem of the Elite missing a command.

[RDS]

@Fireman_Ian

 

Come to think of it, I have had this happen when switching lights on or off but not Loco stopping or starting. With Lights though, you cannot repeat the command because the command is not specific to either on or off. It just changes

 

the present setting, so if the lights are on, it switches them off and vice versa. Under a separate posting, I am currently compiling a list of desirable features and I think I will add this type of thing to the list. Maybe RailMaster should send a slightly

 

longer pulse?

[LMSTim]

RailMaster cannot determine the duration of a command pulse. RailMaster only issues commands to the DCC controller. It is the latter that controls the duration of any command, power or pulse subsequently sent to the track and accessories.

 

Also,

 

I run a layout with six or seven trains running simultaneously, with around 30 different points firing during programs (possibly up to 200 times during the program run). All of it works fine with single commands being sent. This means that RailMaster and the

 

Elite (which I'm using) definitely have the capability not to miss commands. My Master Program must easily end up with at least 500 program lines (merged from five programlets) using the Chain command.

 

That means that we need to look elsewhere for potential

 

problems. I have found that the quality of the USB cable can make a massive difference to the commands getting through to the controller each time, every time, or not. I now use a 50cm shielded USB cable. I also ensure that the Com port number is below 5,

 

as 5 or above are virtual ports and Windows needs to do more work with them. You can easily force a port setting or 1 to 4, which use hardware interrupts and addresses.

 

It is also important to ensure that the settings in the Elite driver (Windows Control

 

Panel) exactly match the settings in RailMaster i.e. 19200, N, 8, 1.

 

Finally, when I run the complex programs on my layout I ensure that my PC isn't wasting valuable processing power and memory on other things, so I ensure no other programs at all are

 

running and the taskbar, which aren't needed (like programs that constantly check the Internet for updates) are disabled. It works a treat and I'm using a ten year old Celeron-based PC with Windows XP and 2Gb RAM!

 

[Gregd99]

LMSTim said:
Also, I run a layout with six or seven trains running simultaneously, with around 30 different points firing during programs (possibly up to 200 times during the program run). All of it works fine with single commands being sent.

What one of the previous posters said was that railmaster automatically sends two command to points. This was what sparked my interest. Another poster said that he doubles up commands at the program level... this could end up in 4 commands

being sent.

This means that RailMaster and the Elite (which I'm using) definitely have the capability not to miss commands.

The Elite actually does randomly miss commands. I spent a long time trying to characterise the behaviour

but couldn't find a pattern. I couldn't find one. I have protocol traces; emails to Hornby; test reports..... The elite just occasionally - can be up to 30% without any retry mechanism - misses commands.

What I did find was that it was very rare that

it would miss two commands in a row. I am guessing that Railmaster implements a double command and it works pretty reliably. The approach that I took was to look for the ACK from the elite within a certain time and otherwise retransmit.

My

Master Program must easily end up with at least 500 program lines (merged from five programlets) using the Chain command.

My programme is around 10,000 lines of Jython..... but that's not the issue. It just comes down to random failures. The control

programme needs to take some extra actions to assure the reliability of the comms. This should all be invisible to the user program that you enter.

anyway.... it is great to hear that it works well for you and you are having fun with Railmaster.