Point to point

When you do Point to Point how would you set it up to slow down realisticly rather then sudden stop? This DCC++ project is pretty cool. I purchased a motor shield but its  a Sansmart  board and not sure that it is compatible with the published sketch provided with DCC++. I have some learning to do when it comes to the Arduino.

Point to point

Rob - There are two ways you can start & stop slowly.  You can set acceleration and deceleration in the DCC decoder or you can have the Arduino throttle that I designed send ever lower speeds until it stops & ever higher speeds till it reaches the set speed.  I opted for the first option but could easily implement the latter in software. 

This link talks about the rate CV  http://www.dccwiki.com/Acceleration_Rate

I am not sure about the Sainsmart motor shield but this one from eBay works well......

http://www.ebay.com/itm/310787745501?_trksid=p2059210.m2749.l2649&ssPageName=STRK:MEBIDX:IT

With shipping less than $8.00

dave

Interesting

Getting to your booster. From the video, I am seeing you take track output and use it as an input to your booster. I am assuming I could take track power from any system (in my case an NCE PowerCab) and put it into your booster? My electronics is quite rusty and out of date and from the schematic I think I understand but want to make it crystal clear before I jump in and start buying parts.

Booster connection

Greg - the booster will take any DCC signal that normally goes to the track.  It uses that voltage for power for the Arduino and for the DCC pulses that carry the instructions for the trains. 

You add your own DC power supply to the large H-Bridge.  That's about it.

I have not tested the booster with NCE but it works well from Digitrax and DCC++ so it should be A-OK!

Good luck with the build and let me know if you have any questions

dave

As I said, I am rusty. It's

As I said, I am rusty. It's been over 20 years since I experimented and built anything. But I am very excited about this.

One question, where is the +5v for the Amp adjusting pot and the display coming from?

5 volt power

Greg - that comes from the output of the LM7805 voltage regulator that feeds power to pin 21 (VDD) on the Arduino - I guess I could have connected those two together!  The 7805 drops a DC input voltage to a 5 volt level - the caps on either side help to filter the output and keep the regulator stable.

dave

One more question

I am confused about the inputs for the display. A4 and A5 it says but I don't see an A4 and A5 on the Arduino.

I think I got it

I may have answered my own question. Looking at an actual Pro Mini I see A4 and A5 on the board. Is that where the LCD display hooks to?

??

 What is the purpose f all this?  Are you making a throttle?  a control for a large scale engine?  What's the purpose?

LCD hookup

Right you are, Greg - the library that I use with the LCD display is coded to use those two pins - on the Pro Mini they are not on the edge but in a bit -  Good job discovering that!

dave

What is the purpose of all this?

Hi, Dave - I guess the purpose depends on where you are coming from -

- For me it is an opportunity to learn more about DCC, electronics, programming and train control

- For some it is a change to experiment with a DCC controller for less than $20.00

- For others it is an interface that allows you to detect and control trains using a microcontroller so that you can build an automated layout, be it a simple point-to-point or a set of switch-backs that climb up a mountain.

As you may have noted from some of the links I provided I have built up a DCC throttle that connects to the DCC++ unit that allows me to control trains.  It also can be set to operate a trolley on a point-to-point line.  The options and possibilities are only limited by one's imagination & skill.  Kind of like the reset of model railroading!

dave

Components

I've been sourcing and pricing components. By far the most difficult thing and most expensive is the power supply. Still working on that. However it is interesting I can source something like a transistor or diode in Canada for between a dollar and a dollar and a half (plus shipping) but on eBay I can buy 100 for $2.50 from China with free shipping... Insane.

Another question. Your arduino is mounted on a board with several other components. Where did that board come from? Is it something you made?

Board for Booster

Greg - the circuit board that I used for the booster is from another DCC project that I did a year or so ago - rather than using a prototype board and soldering all the connections I repurposed that - I have a few extra - I would be happy to send you one - drop me an email (dave@davebodnar.com) and give me your address.

I'll have to build up another booster and take photos along the way so that you have something to work from!

dave

This is Cool!

This is great, I have an Arduino that I am starting to learn. Even though I have a satisfactory Digitrax system, I may have to build one of these just for the fun of it. My electronics knowledge is pretty limited, but I will try it anyways!

Thanks for posting.

Power Supply

Greg - what voltage / amperage power supply are you trying to find?  For many applications I use a retired laptop power supplies - You can find them that range in voltage from 12 to 19 volts are up to 3 or 4 amps.

dave

Go big or go home

I was looking for 18v and 10a but I realize this is likely unrealistic. Something 5a would suffice. I think I found something on eBay in the 20 dollar range for use with LED lights. 18v 5.5a. 

Motor Shield

I ordered the motor shield you suggested. Its on the way and I am excited to try this DCC++ out.

Keep us posted

Rod - let us know how things work for you - don't forget to cut the trace under the motor shield (labeled VIN) if you plan on feeding more than 12 volts to the shield - I have a photo of it on my web page, here:

http://www.trainelectronics.com/DCC_Arduino/DCC++/index.htm

It is also shown below.

dave

DCC++ WOW

Hi Dave,

I have always been a do it yourself kind of guy. My first project regarding train control was to build the CTC-16 system that was posted in Model Railroader magazine 1980-81. That was a very involved project and I never did get it working. After getting away from the hobby for many years I found a website online that explained how to build a DCC system. That was the Nano-X system on Paco Canada's site. http://usuaris.tinet.cat/fmco/home_en

The Nano-X is pretty cool and I built two of them for a total cost of around $50.00 each.

Now comes DCC++. I purchased An Arduino Uno For less then $5.00 and a  motor shield for $5.00. I have several power supplies kicking around. So for around $10.00 I now have a working DCC++ system. I got the motor shield in the mail yesterday and had the  DCC++ system working within an hour. Most of that time was watching the online videos. All I can say is WOW! 

I will be taking this DCC++ to our annual Train show and use it for the Test track. I expect it will be a big hit. Past shows anyone wanting to test DCC equipped locos was either out of luck or maybe they would have to talk one of the club layout group to test for them.

Big Thank You,

Robert Teed

Railyard Productions

Thanks for letting us know you got it working so quickly!

That is great news, Rob - I have been very impressed with all that you can do with DCC++ for very a very small investment.

Keep in mind that the basic motor shield is only good for an amp or so, but that should be plenty for testing most locomotives, even G-scale ones.

I have a controller built up that can easily handle five to ten (or more) amps so power is not an issue for me - the additional hardware costs all of $12.00!

Enjoy!

dave

Just gotta try it

The Arduino DCC controller is so elegant - two boards and done - seems too easy. The I looked for a 15 V power supply and as was mentioned, a laptop supply of 15V 5A is less than $10 from Amazon.

Going to have to try this!

Going to have to try this!  Just getting into DCC, love tinkering with electronics and programming.  Thanks for sharing!  

Arduino

While I have used the Arduino Uno because thats what I had on hand you might consider the Arduino Mega. Its a bit more expensive but probably a better way to go. Just my 2c worth.

Mega it is

Yes, I had viewed the complete set of videos for hardware and software and  planned on using the Mega.  The extra digital outputs of the Mega will be immediately useful for turnout servos.