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    • February 23, 2018 7:02 AM EST
    • After viewing David Bodnar's video and page on the adafruit NeoPixels I think I'm just going to put a toe in the water and buy one of their smaller microcontrollers and maybe an array panel rather than a strip and start experimenting. I think I read that some of their microcontrollers have Bluetooth which interests me too for wireless remote.


      But first, I need to get back to working on Martin's beta of his Bluetooth RC/DCC locomotive control.  I got a really bad idea last night while playing with it which I will share privately with Martin, but it might get me back into building electronics.

    • February 21, 2018 9:59 PM EST
    • Thanks David - I will read your pages and check out the video. The NeoPixels products were referenced earlie They are cool - driven by a single wire data line. Each LED is uniquely addressable

    • February 21, 2018 1:16 PM EST
    • Good day - I spent some time experimenting with similar LEDs and have some notes that may be of interest on my web page - there is a YouTube video, too

      The LEDs that I worked with are not driven by PWM but by the Arduino sending data directly to a controller on each RGB LED - very cool technology!

      Please let  me know if you have any questions.



    • February 21, 2018 11:01 AM EST
    • For your LED project, my understanding is that you need to generate 3 PWM signals - red, green, and blue - such that the duty cycle of each corresponds to the contribution of that color to the composite color you're after.  These will be logic level, so you need a transistor driver for each to interface with the strip.  

      To get started, once you've worked out the hardware, take a look at the analogwrite() function for the Arduino and other compatible platforms.



    • February 21, 2018 9:03 AM EST
    • This is quite a rabbit hole.  I spent 15 minutes just looking at the product page on adafruit.  Need to read thier how-to pages to get a better idea of what they have going on.


      I never did any programming in C. I was pretty strong in Basic before VB came along - I never made the jump to the GUI based stuff.  I did some very light assembly programming back in the 80's just to get a function I could call from Basic.  I don't even remember the project, but at the time I was running a TRS-80 Color Computer with OS9 - another Unix derivative.  It's interesting to look back now on how Multi-user was the rage then the way cloud computing is now.


      Bottom line is I have the aptitude, just don't know if I have the discipline to learn new languages.  On the other hand, it looks like there is a lot of open source stuff out there and learning to modify for personal needs may not be as daunting as writing from scratch.

    • February 21, 2018 8:40 AM EST
    • I suggested the Pi Zero simply because it's only $10.  Obviously running a linux box for controlling LEDs would (normally) be overkill, but at $10, and considering the setup to get going on Ardunio, it's a wash in my view.  It also lets you program in python and has built in Wifi.  So you could, in theory, setup a self contained network and web server to talk to your phone to turn your LEDs on and off.  That's pretty impressive for a board about the size of two postage stamps.


    • February 21, 2018 6:52 AM EST
    • I hadn't thought about CP/M for years, but I was just getting nostalgic for my family's first PC, a Kaypro II, the other day, and watching videos of it on YouTube.  I was a kid in the 80s (41 now), and grew up alongside the personal computers.  The Raspberry Pi really feels like going back to those days.  I love the accessibility of the hardware and terminal style interface.  I'm glad that kids now have something like that available.  Also, being a Mac user, it's easy to go back and forth between MacOS and Linux since they are both Unixes.  


      The Arduino, ESP8266, and many other microcontroller platforms are typically programmed in C++.  The ++ is the object oriented capability, but if you've done any C programming, even 30 years ago, you'll recognize the syntax.  When I first used microcontrollers in the 90s, it was all assembly.  I couldn't believe how far things had come when I got back into it 15 years later.

    • February 20, 2018 11:39 PM EST
    • On Saturday, Feb. 10, at the Bay Area Garden Railway Society (BAGRS) annual meeting (after I gave my presentation on Body Mounting Kadees) another presenter Seth Neuman, of Model Railroad Control System, described what they used (the Arduino microcontroller run with "Sketches"-  a C based software so he said) along with various sensors they have.

      Has anyone looked at or used any of the Model Railroad Control Systems products?


    • February 20, 2018 10:49 PM EST
    • I’m like Jon, experience but it goes all the way back to CP/M, never went much beyond MS-DOS and Windows 3.1, but I am really interested in seeing what this stuff can do.

    • February 20, 2018 10:32 PM EST
    • Thanks for the suggestions guys; I'll check that stuff out


      I'm not exactly a beginner, just 25 or more years behind. My brother in-law and I were networking TRS-80 model 3 computers over an RF link (27Mhz) in 1982. I've done some hardware dabbling and computer programming, but it's been a long while. I've played with Unix and Linux and PC OS from ROM Basic and MS DOS through Win 10.  Very little on the Apple side except some 90's hardware tech training.


      Glad y'all realize I am a noob when it comes to the current crop of stuff. I been watching the SBC's for a few years but never dug in.  I've had microcontroller experience as an end user in several RR R/C products.


      I'm thinking the microcontroller might be more suited to what I'm up to. My only problem there is programming. I'm nowhere with current languages.



    • February 20, 2018 9:43 PM EST
    • They are really cool and have a lot of great uses. I have 5 Raspberry Pis running full time doing specific tasks that are too intensive for microcontrollers  But it’s a lot of overhead for a beginner, particularly for a project requiring hardware I/O!

    • February 20, 2018 9:27 PM EST
    • Normally, I would agree with Eric here but I just got a Raspberry Pi ZeroW for 10 bucks so I'm re-thinking my perspective.  A cheap tiny computer that runs a linux operating system is pretty cool :)

    • February 20, 2018 8:50 PM EST
    • The Raspberry Pi is not a microcontroller.  It's a single-board computer (SBC).  A microcontroller is a microprocessor with some program memory that runs a single program over and over when you power it up, while a SBC has an operating system, file system, etc.  Most SBCs run Linux, including the Raspberry Pi.  To get it to do something, you need to boot it up and run a program.  The SBC is much more powerful and versatile than a microcontroller, but overkill for a lot of projects.  Microcontrollers boot instantly and can be turned off at any point without worry of corrupting the file system.  With Linux, you have to shut down the computer when you're done using it.


      For what you're interested in doing, I'd go for a microcontroller without a second thought.  There are several, such as the one Dan linked, that have networking capabilities and other bells and whistles.


    • February 20, 2018 7:29 PM EST
    • Not sure this counts, Jon, but I am using a RPi connected to an Arduino Uno to run a CNC router system that I am building.  Its all new to me so I won't be a lot of help, but I am interested in where this thread goes.

    • February 20, 2018 7:18 PM EST
    • Inspired by Kevin Strong's use of RGB LED strip lighting on his Path Valley Railroad, I started looking into sources for them.  Most "kits" come with a small power supply and a controller that uses a hand held remote. That would work for me, but I'm thinking this may be my opportunity to start experimenting with microcontrollers (Raspberry Pi, etc.) to power them plus set and remember scenes.   There are systems available that use a WiFi controller and a phone app to do similar, but I'd just as soon roll my own.  I don't necessarily need wireless control, but it would be OK, especially if I could just say "Hey Alexa (or Yo Google) set the railroad lighting to Late Night.


      Problem is I have no idea where to begin.  Anyone played around with this at all?

    • January 2, 2018 4:46 PM EST
    • H bridge is really the design, where the schematic looks like an "H", although you can buy an IC that has an H bridge circuit inside.

    • January 2, 2018 3:41 PM EST
    • Thanks - I guess my terminology hasn't caught up with my idea factory.  What I was calling simply an H-Bridge is really a "Single channel H-bridge speed controller - 10A, 6.5V to 28V"  So I are now a bit more edumacated.  Thanks!