Coding

Making Adafruit Pixel Goggles

Let me start with the motivation for this project. On one hand, I had never really created a solution with a micro controller, and on the other I wanted to create a cool Halloween costume. The rest of my family was getting dressed up in steampunk outfits, and for a change, I wanted to add something to the mix. But, to do this, I was going to have to learn how to program this micro controller, solder, and how to get the code on the NeoPixel. I know that some people would laugh and say that this would be an easy project, but when you have never worked on this before, it is a completely different case.

Enough back story, time to walk through the build process. First, there are a the items that you will need to build out the entire unit. You will need a soldering iron. That is if you want to make it permanent. Otherwise, you will need a pair of goggles, 2 Adafruit NeoPixels, and an Adafruit Trinket. You also need a portable battery and a hookup to provide the power to the NeoPixel rings. I can break down the list and links, but they may go bad after a while. There is also a kit

There are instructions on the Adafruit website, but to be honest I found them a bit difficult to follow. There was some difficulty in understanding the instructions and what they were implying. They did have a very nice diagram that was of more use than the rest of the instructions. And, given everything, that is all you really need as far as laying out the wires.

First action is to solder on the JST-PH 2-Pin SMT Right Angle Connector to the Trinket. The USB power to the Trinket is not enough to power the NeoPixel Rings. As a result, you really need to hook up the connector so that you can provide a 5v power supply to the Trinket. Don’t make the same mistake that I did and hook up a 9v battery. This will be to much power, and the rings will only work sporadically. There is a technical reason for this, but I don’t remember electrical theory to explain it. I know enough to know that it will not work right.

Once you have the power supply soldered onto the back of the board, then the fun really begins. The power supply connectors are on the back and this is where you have to connect the adapter. There is a way to test the power supply, and that is to load the blink code onto the Trinket. I will make sure that is in my code sample. At this point, you should have a trinket that has a power supply hooked up to it, and the ability to push code to the Trinket.

That is one thing that I should have touched on. It was a huge pain to get the code to push to the Trinket when I first started working with it. I ended up have to install a very specific version of the Arduino development plaftorm, version 1.8.5, in order to get the libraries to work. In retrospect, I would have seen if I could have found a Trinket M0 board. That board is supposed to support python, and has more options when it comes to the IDE. However, as of this writing, I had to use a specific version of the Arduino IDE, but I was able to get all of it working. Just remember, that sometimes compiling the software first before pushing the button to sync makes it easier to get it all done in time.

The next thing to do was to hook up all the wires and see if it would work. Seeing as this was my first time working on the Trinket and with the NeoPixels I was not sure if I was going to get the wiring done correctly. To ensure that I was doing it right, I decided to use wires with (sic) roach clips to validate the circuit that I was going to make. At first I was intimidated by the circuit, and thought I was going to mess something up. In retrospect, it was pretty simple. 

First, lets talk about getting power to the rings. On the one side of the Trinket you have 2 connections. One connection is for outgoing power and the other is ground. There may be a technical reason for the name ground, but the simple part of it is that you need to create a complete circuit. This means the power goes from the power output on the board and goes to the power input on the NeoPixel. Then, then ground needs to come back to the board to complete the circuit. To add another ring to the mix, you take the second power connection from the NeoPixel and connect it to one of the power points on the other NeoPixel ring. Then hook up one of the ground connections to the second ground connection on the first ring. Bam! Power to both.

That is great and all, but you need to get the data to the rings. For this, the rings have a ‘data in’ and a ‘data out’ port. Unlike the power connection, this does not have to complete an entire circuit. You just select the outbound pin you want to use from the Trinket and connect it to the data in slot on the first board, then you connect the data out connection from that board to the data in on the second board. That is all. I thought there was more to it. There is not.

I will be the first to admit that I did a horrible job at soldering. It was my first time, and I had the temperature set to low, and then I had the wrong power level, so when I thought it was wrong, it turned out to be right, and I redid the entire thing. Don’t be me. Make sure you check the power 6 times and test after every solder. Unless, you are like a friend of mine. He had a job doing soldering, and he is a godlike at it.

The last part is the code. Ah, this is much more fun, and I think I might come back and revisit this later. Needless to say, the samples are here. I am a big fan of github and bitbucket for storing and sharing projects. That is a song and dance for a different day.

Micro controller Hacking coming soon

I have been hacking on my costume, and as such, have not gotten around to posting the code and pictures of the project that I am currently working on. As soon as Halloween roles by, I should be able to get that up here. Hopefully, you will enjoy the costume and the work that I have done on getting the goggles up and running. 

Normally, I would have tried to add it in chunks, but I have been learning how to solder, learning how to code this thing, and have been trying to get the rest of my costume configured. 

That being said, I am working on it. Oh, and for work I have been learning all the new nuances to python 3.6. Almost like learning another language from what python used to be. So, hold out for another few days, and I will share my code and some pics of the work as I have learned how to solder, and how to write a bit of code for an adafruit neopixel.

Configuring AWSCLI and Python on Windows

Trying and doing stuff on a Windows 10 machine has become a rather interesting experiment. It started as a place to be able to play video games and have access to a few programs that are not easily available on Linux, to a test of seeing if I could now do all the things on Windows 10 that I could do on Linux.

Turns out, I wanted to test out the Cloud Directory service from AWS. I figured the 2 easiest ways to do this would be via the AWS CLI and Python. It did not occur to me that I had neither of these installed until I opened up Cmder.exe and typed 

aws
and then 
python
and both came back with the not found.

Wait, what? Where are my programs!

So, now I need to install and configure both of these. The test is to see how easy or difficult it is to get this setup on this Windows machine. Quick list of the normal steps that I take to install the AWS CLI on most any Linux machine.

  1. Install Python
  2. Configure a virtual environment to hold my cli tools
  3. Use pip to install aws cli
  4. Configure aws cli
  5. Test that it all works

The first step in setting all of this up is to get Python installed on your machine. The AWS cli is based on Python, and as such you need to have python installed in order to use it. Now, there are some that will install the AWS cli to the root of the machine, and use the system’s globally installed Python. Due to having worked on multiple versions of Python at the same time, and projects that use different libraries, I almost always setup an Virtual Environment to run my Python programs and other sundry programs from. This way, I don’t cross contaminate my streams, and have a clearly defined idea about which versions I am using on different projects.

Installing Python

This is a relatively straightforward task. Click on the Python installer that suits your needs, download it, and follow the install prompts. I chose Python 3.6.7 because it is the version that I am already using when running some Lambda programs in AWS, and because there are some new changes in 3.7 that have broken a few other libraries. On big one is ‘async’ and ‘await’ now becoming keywords. Follow the prompts to install Python and the restart your favorite command line tool. I run bash via git, and use cmder.exe as my shell program.

Once you have it installed you should be able to run the following to verify that you have install python on your workspace. python --version This should output ‘Python 3.6.7’ or whichever version of  Python that you installed.

Setting up Virtual Environment and AWS CLI

The next part is to install the virutal environment and to then use that to install the aws cli. This should be able to be done with just a few commands, and then you should be up and running.  First we run python and install the virtual environment. Then we activate the environment and install the AWS cli. It is just a few simple commands, and you should then be up and running.

c:\ericv\dev\python -m venv p367
c:\ericv\dev\> p367\Scripts\activate.bat
(p367) c:\ericv\dev\> pip install awscli
(p367) c:\ericv\dev\> aws help

And bamm! you are done. Now, there is always configuring aws to use params, but that is another issue. But, it took me longer to write this up, than it took me to do the install.  That in of itself is a good thing to know. Now, the question is if I will run into any more problems. But, so far so good.


Time to Hack On an Adafruit Trinket

I don’t know much about microcontrollers. Somewhere along the lines, I never learned about them, how they work, or how to wire them together and use them. Up until a few years ago, I did not even know what a bread board was. Heck, I still do not even really know how they work, but I am going to learn.  And to that ends, I am starting with an Adafruit Trinket.

Let me start by saying that I have hooked up an arduino microcontroller, and turned a light off and on, but that was the extent of it. Without having some other sensors I did not see the point. As a result, it ended up collecting dust on a shelf for the past few years. I did have some ideas of some projects that I wanted to do, but I had no idea where to start, or what tools I would need.

Those are all pretty much excuses. In the end, I never took the time to learn the various parts of electronics. Now, I plan on diving into the world of microcontrollers and see what I can create, and if I have any desire to continue on with it. Could be that I finish a single project and decide that there is nothing else I would like to build or tinker with. That is one of the fun things about trying out new projects and activities, you can find what you enjoy and what you do not.

As to how I am going to start, that is simple. I picked up a project to do. Using some items that I already own, I am going to start learning how to program an Adafruit Trinket. Along with this, I got a couple of the light rings that Adafruit also sells. One of my main issues with arduino, is the cost. I don’t want to have to dish out $40 for just the board for every project that I plan on working on. 

So, now it is time to go play, and to learn. At least on this topic. But, it is good not to do the same thing all the time, and to keep things interesting. I will add updates as I continue to work on my project, and maybe include the final product.