Fun with Robots, IR Decoding, LED Matrix, etc.

Fig 1: Three experiment--two with the samsung remote on the left, one with the Radio Shack remote on the right--to control a +Adafruit Industries 8x8 Bicolor LED Matrix

I haven't posted in a while because several interests have kept me very busy. This all started withe the +Parallax Board of Education (BOE) Robot kit. I asked for and received on for Christmas a couple of years ago and let it ripen until I was ready.  I decided that it would make a good project to do with my 7-year-old granddaughter when she visits this summer--but first, I should make sure that I can build it without a lot of fumbling. Fumbling is good, but watching me figure out what dumb thing I did is not always interesting to a 7yr-old. I followed the tutorial and learned quite a bit, The last project that I did used infrared for proximity sensing to avoid obstacles. At the same time, +Adafruit Industries, via The Desk of Lady Ada, provided some great information on IR. So, I decided to play and learn further.

Fig 2: +Parallax BOE Bot with 2 IR transmitters aand 2 IR receivers

IR Decoding the Hard Way

Following the +Adafruit Industries tutorial on IR Sensing, I was able to decode only some of the buttons on my Samsung TV Remote (see Figure 1). Using the remote is a 2-step process: first decode the signals send by the buttons, then use the decoded signals in a different sketch that takes action based on the buttons. Using this method (see the Raw IR Decoder and ircommander code on github), I was able to decode some of the buttons and use them in a sketch.  

Quick diversion:  I have had big plans to use a 32x32 LED Matrix that I bought in a parking assistant project that will display faces to convey the emotions evoked by a car getting increasingly closer. I decided to use the 8x8 bicolor matrix and backpack to prove the concept, and use the remote to signal which face to display. Figure 1 shows the initialized yellow face (looks orange to me). So, I needed to follow the tutoral for the matrix and backback library.

I was able to merge code from the bicolor8x8 example code in the Adafruit LED Backpack library with code from the ircommander sketch referenced above. After adding the decoded remote buttons to a newly created library (see the IR Sensor tutorial and the project video cited at the end of this post), I was able to change the face on the matrix based on the remote buttons.

I found both the coding aspect and the operation of the technique to be less than perfect.  Maintaining a separate library with very long sequences of numbers just to test what button  was pressed seems a bit much. In operation, the code seems to reset itself randomly, and only respond to buttons when it feels like. This may be me, and I will investigate, but read on to see a much neater technique.

IR Decoding an Easier Way

After working through the above, I watched Lady Ada work through Chris Young's IRLib2 in one of the Desk of Lady Ada epdisodes cited above.  Chris, aka cyborg5, is a frequent visitor to the Adafruit Show and Tell, and has done a lot of great work (see his blog).  Both the decoding and the processing techniques are simplifies greatly, and his library handles several IR protocols. The IRLIB2 tutorial describes it all very well.  You wind up with one simple code that you supply in a sketch so you can determine what button was pressed--straightforward, and I was able to decode all the buttons with no missed presses. From there it was a matter of simplifying the sketch I wrote earlier to display faces on the LED matrix.  Again, the project video shows all this.

Controlling Motors with IR

Since we started with robots, I thought it would be interesting to control motors with IR.  It was a simple matter to modify the IRLib2 sketch above to direct the continuous rotation servos.  I took code from the BOE-Bot project, and code from the Adafruit_PWMServoDriver library tutorial, and it went smoothly.  The servos in the BOE-Bot are different from the Adafruit ones, so I had to go to the data sheet to see what values to use to get them to move as I wanted. I was able to decode all the buttons on the Samsung remote, and used the arrow keys to simulate moving the robot forward, back, left, and right.

I first did this without the PWM Servo FeatherWing. Because the feather is 3V logic, I needed a level shifter to handle the signals from the board to the servos. That worked, but added a few connections and I used the Arduino servo library as opposed to the Adafruit library which allowed for simpler code.

Another thing I needed to worry about was timer conflicts. I had come across this before, in my Donkey Project, but Chris' tutorial gave a straightforward explanation and solution. The problem is that the servo library uses Timer1 and on the 32u4 Feather IRLib2 does too. It was necessary to go into one of the associated libraries and change one line of code to re-assign the timer.  You'll get better instruction in the tutorial than I can give here.  Again, the project video shows the results.

Controlling 2 FS90R continuous rotation servos from an Adafruit BLE Feather and PWM Servo FeatherWing

Trying a Different Remote

A while back, Radio Shack sold some MAKE project kits, including robotics. During an earlier RS bankruptcy, I acquired a RS remote at a big discount and still had it in inventory, so I decided to try it out. Using the IRLib2 approach to decoding, I found the the protocol was not one of supported ones. A look at the datasheet for the PT2248 chip in the remote revealed that ot used the Toshiba protocol. So, I had to go back to the hard way, and I got that to work.  See the video.

IR Affects the BOE-Bot

Just for grins, I took out the BOE-Bot, let it runon the floor, and chased it with a remote.  The bot's IR retrievers detected the transmissions, and the bot reacted accordingly (moving left or right as if it had detected an obstacle).

Project Video

See the project video on YouTube

Andy's Ham V20 Virtual Machine Update

When last we left Andy's Ham, in this post, I had Andy's linux ham radio distribution installed in a virtual machine running on a Windows 10 host under Virtualbox. The installation was successful, but I still had to run some software.

The first step was to get the virtual machine to recognize my my Signalink USB. After starting up the VM, in Virtualbox, I went to "Settings/USB" and found "Burr-Brown from TI USB Audio Codec." I ticked that, and for a couple of weeks I could not get the VM to do anything but freeze up.  I was pretty sure that that was the Signalink, so I scoured the interwebs for information, to no avail. In desperation, In installed AndysHam on a different physical machine and plugged in the Signalink. The same option appeared in USB settings, and it worked. This time I notice the options for USB controller: 1.0, 2.0, and 3.0.  In both cases I had ticked 2.0.  However, the computer with the VM has some USB 3.0 ports (see this post on my upgrade). I had not noticed that I had plugged the Signalink into a 3.0 port (I just reached around to the back of the computer and plugged it in where I could). I went back and ticked 3.0 and all was well. The VM did not freeze and the Signalink showed up as an option in the software (fldigi and WSJT-X).

VirtualBox USB settings for Signalink (be sure to enable the correct USB controller)

If I have WSJT-X (e.g.) running on the host, the guest grabs the USB port for the Signalink and holds it until the VM is shut down. So, I can run the software on the guest, but not the host. On the host, the Signalink is not an option for sound card until the guest is shut down. It may be necessary to redesignate the sound card every time--however, if you plan to use the Signalink in the guest only, this is not an issue.

So, I got AndysHam to work in two environments--on a stand-alone machine and as a guest machine under Virtualbox.  There are a couple of things I need to get used to. First, JTAlert does not run on linux.  I have been enjoying the features, so I'm not sure I want to give that up. Second, I find the set up a little inflexible.  I'm sure I can do what I want to do, but it's been set up to provide most things, and for under-powered computers--which mine is not.  

I'll work with it some more, and if I have anything useful to say in the future I will post it here.

Andy's Ham Version 20 VM Installation

I have recently made progress with digital modes.  On 2 Meters, I have been successful with packet on my Alinco DR-135. I am considering a Tigertronics Signalink as sound card interface for my Ten Tec Jupiter.

Meanwhile, I need software.  I could pursue commercial options like Ham Radio Deluxe, but I decided to explore some free options.  I discovered KB1OIQ - Andy's Ham Radio Linux .  The advantage is that it includes a variety of free packages, including logging, rig control, satellite tracking, and a variety of others.

I had 3 options for installation:

1. Turn my Windows 10 system into a dual boot, and boot into linux when I want to play radio and Windows for other applications
2. Install Andy's Ham on a separate matching dedicated to playing radio
3. Install Andy's Ham as a virtual machine (VM), running under Windows

I chose option 3, because dual booting can be a pain and a separate computer can add complexity. Running a VM allows both Windows and linux to be available at the same time. To do that, I needed virtualization software. I chose VirtualBox because I have used it before at work and home.  Installation on Windows is simple: download the correct version at the link just provided, and run the .exe.  It makes sense to download the Extension Pack and install it, too (honestly, I don't know why that's an option--just always install it).

Once VirtualBox is installed:

1. run it and create a VM (follow the prompts--consult the user documentation at the download link if you need to). The only change I needed to make from defaults was disk size--it defaults to 8G but I gave it 20G--Ubuntu says it needs ~20. 
2. download Andy's Ham (link in the second paragraph above)
3. in VirtualBox, click settings, then storage for the machine you created. Next to Optical Drive on the right, click on the CD image and point it to the downloaded Andy's Ham .iso file.
   

   

   Installing Andy's Ham in a VM
4. Start the VM--follow the current instructions. For me I chose the "live" option when prompted. When asked for a user id gave it "ubuntu" and presses enter on password (no Password). Once the VM comes up, you can play with the installation, but nothing is permanent until you install to the VN's hard drive. To do that, click on "Debian"  at the lower left, an in the menu that pops up click "System" then "Install to Hard Disk."  This will take a while, but cannot run unattended because you need to respond to some prompts along the way.
5. Restart the VM (click on machine/ACPI shutdown, then double click the machine name), and you're done.  One of the prompts you responded to created a user and password--use those to log in to your new machine.

This is a nice remix of Ubuntu if all you want to do is play radio.  I'm going to have to play to see how to add back some Ubuntu features that I'm used to.  I will post again after I've had a chance to play/learn.

Install Andys Ham to hard drive after starting with "live" option

Example of how to navigate to some of the features

I upgraded my computer--including stupid technician tricks

System Information (from Control Panel/System)

The last two times I was on +Adafruit Industries #showandtell, my video was unacceptable.  That's a minor irritation for me, but the second time I had my seven-year-old-granddaughter on. She was able to get through it, but it was a struggle.  Show and and Tell is a Google Hangout, and the minimum requirements include a quad-core processor.  I had been getting by with an AMD Athlon X2 dual-core processor and ASUS Motherboard for the 3 years I've been participating by shutting everything else down and running just one tab on Chrome for the hangout, but I guess Google's "enhancements" have rendered my computer obsolete.

The computer was an 8-year old home-build, and has served me well, but I decided that I needed to get my granddaughter on again in fine style, so I bought an AMD 8-core processor and ASUS motherboard. Actually I bought an ASRock motherboard first, but I had some issues with the build (see below) and I read reports of this mobo bursting into flames, so I returned it and ordered the ASUS. I will report here after I try Show and Tell again, but so far it's great.

Additions

I also ordered a new graphics card.  I'm not very happy with it. First, the description, the invoice, and the parts list all say it supports DirectX 12.  What Newegg sent me supports DirectX 11.2, according to the box. I returned it for replacement, expecting them to fix their error right away.  It turns out that they refused to replace it until the receive the one they sent in error.  So, I changed it to refund and ordered a new one.  I got the new one 5 days before they received the return. To my surprise, it was the same version. Newegg has been good in the past, but this is not good.  Over 2 weeks later I still do not have a refund.  

In addition, I got this card because Microsoft says that the Windows 10 video capture tool works with AMD Radeon R7 and later. However, it's still telling me that my video card is not good enough for them. More research.

The motherboard has an  M.2 slot for what is essentially and SSD stick.  When I get around to it, I will add a 250GB SSD using this new, smaller, faster technology.

The motherboard also has COM header for a serial port, Since my ham radios are able to work digital modes through a serial port I ordered one from China and will hook that up to enable me to experiment with digital modes. More learning and excitement!

Since the 650W power supply I had in the machine had failed recently, I had replaced it with a 800W supply.  Underpowering a system is an invitation to frustration, so if you're upgrading, don't forget to be sure that you have a power supply that will meet all the requirements of your new system.

Stupid Technician Tricks

I won't go into detail on the big one (it's embarrassing and I know better), but here are some suggestions for installing an AMD CPU on a motherboard:

1. lift up the lever next to the pad on the motherboard
2. align the arrow in one corner of the CPU with the arrow on the motherboard pad (also check the pattern of the CPU pins to be sure they align with the pattern on the pad
3. only after the CPU is seated properly, push the lever down
4. check that everything is secure BEFORE adding the heatsink/fan assembly

Enough said, except that the overarching recommendation is "Take your time!"  

The only other problem I had was minor:  the hard drive light was not lighting. Obviously, I connected it wrong.  Lesson: double check your connections before you plug in the unit, and check that everything works before putting the case all back together.

Activation

Initially, I thought I may need to buy a new copy of Windows, but I read up on Microsoft's digital license policy and made sure that I was all set up.  I had Windows 10 Pro, installed as part of Microsoft's free upgrade program. Since I had purchased Windows 8.1 Pro, it upgraded me to Windows 10 Pro.  After I fired up the  machine I was not asked to activate Windows (although Office 2010 did ask to be activated--quick and easy).  I did get a message "you need to fix your Microsoft Account."  Google revealed that I needed to update a user. When I went in to do that I was told I couldn't because Windows wasn't activated.  I went through the activation process--which tells you you need to buy a new copy but has a non-prominent link "I recently upgraded my hardware."  I clicked that, and after a couple of "our servers are down" messages, I was able to activate.  Done,

I use Norton Security provided as part of my subscription to Comcast.  Norton said it had expired.  I couldn't convince it that it hadn't, and Comcast help was typically useless, so I uninstalled it and reinstalled and all was forgiven.

Summary

I have a fast new machine that should work with the Adafruit Show and Tell Google Hangout. Everything is activated.  I have and upgrade path to an SSD and will have a serial port to use for ham radio digital modes as soon as it arrives.  Overall I'm happy with the build.

The only issue is the video card.  I read on the interwebs that others with this card have had the problem Windows 10 video capture.  I'm working on it.

I am an Extra Class Operator

In 1958, my friend Freddy and I studied Morse Code with the intention of becoming licensed Ham Radio operators. Then Junior High School happened, along with the 60's and other decades of distraction, so I never got licensed.  About 3 years ago, I became interested in hobby electronics. In the process I built a crystal radio, and all the ham interest came back. A little over a year ago, I decided to investigate the local ham community.  I found an active, vibrant community so I decided to get licensed. I passed my first exam in January of this year.

As of about 9:45 AM EST 10 December 2016, I am an Amateur Extra Class Radio Operator. I passed the test with a 100% score. I have now taken all 3 Ham Radio license exams this year. I scored 100% on the Technician, got 1 wrong on the General (although when they asked me the question after the test I got it right), and 100% on the Extra.

So, now I have to go learn what the questions really mean--but I am proud and happy, and I have made two QSOs (contacts) so far with my new privileges.

Generator House Upgrades

Upgraded house, showing new roof, exhaust system, and PVC carrying wires to/from the residence.

The generator house (see this post) did a great job.  However, we needed some upgrades.

First, we needed to get the exhaust fumes out.  The extra heat and the flammable gasses were a potential problem. So, with some black iron pipe and some welding (again, my brother-in-law has skills), we fashioned the exhaust system and connected it to the generator.

Next, in order to power the house, we had to run a cable from the generator to the transfer switch--every time.  I bought a new transfer switch with more circuits and more suitable for my house.  We ran 10/4 wire from the transfer switch, and 14/2 from an existing circuit, to a junction box, then out through the wall, where the wires ran through PVC down the outside wall, underground, and into the back of the generator house.  The 10/4 goes to a junction box, where it connects to a cable that plugs into the generator. Now we don't have to mess with the heavy cable every time we want to power the house.  The 14/2 supplies 2 boxes:  one with a switch that goes to a light plus 2 unswitched  receptacles and the other to a switch that controls 2 receptacles--the fan is plugged into one and the battery charger to the other. These will always be powered, except in the time between house power going out and running the generator.

Third, the quick roofing job was not sufficient, so we took off the old shingles, put down tar paper, added metal drip guard around the edges, re-shingled, and added lead flashing at the top.

Now we have something!  When we have a power outage, all we need to do is flip the switches on the transfer switch to off, start the generator, let it run for a few minutes, then flip the transfer switches to generator, and we have power.  The whole house, except air conditioning and the stave and dryer can run off the generator.

BTW, when I say "we" with respect to any work I mean my brother-in-law under my expert supervision (which is mostly me saying "that' looks good").

See the video.

Halloween Candy Cauldron V3.1

V3.1 in the enclosure. Ignore the external speaker--it's a vestige. Ready to tidy up for V4.

As I said in my last post on this project, all that was left to do was tidy up the connections and enclose the electronics. I decided that the enclosure I was using was too big. The reason it was too big was that I had the project on a breadboard instead of soldering the components to a PCB. I have always wondered why places like Radio Shack that sell enclosures and PCBs don't sell PCBs that fit in the enclosures--with mounting holes and screws.  So, I went looking and found this enclosure with matching PCB and a battery compartment. A little pricey, but good quality and they have a variety of sizes and features. (I'm using the term PCB to include proto boards here.) Follow-up note: I found that the soldering pads on the pcb were insufficient.  I'll accept blame for my soldering technique, but I had more trouble with this than any other I've worked with.

Since the new enclosure was a little smaller, I decided to use an  +Arduino Pro Mini (actually an Arducam clone) instead of the +Adafruit Industries Pro Trinket.  It's a little smaller, and I had a few in inventory. It needs an FTDI to serial module to program, but I was using one anyway for the Trinket to be able to use the serial monitor.

The code compiled with no changes.  (See link to last post in opening sentence to see code.) In order to upload to the board, the IDE required some changes (to point to the right board--Nano, not mini), and the USB Port needed a tweak in Windows Device Manager (I'm on Windows 10). Arduino.cc has a clear and concise getting started article describing this better than I can.

Interrupt

Note that the interrupt code also works as-is.  I need to work on the program to make the sleep more useful. As you can see in the video (the blue LED is on when it's sleeping), it doesn't sleep much, I'm using the Echo pin on the HC-SR04 sensor to wake it up. I put it to sleep at the top of the loop, then wait for Echo to go LOW or HIGH. It works the same either way, at least to the naked eye.

I used LOW because IDLE is the only mode that can be woken from anything other than LOW, and I wanted to be able to play with other modes. I'm thinking about using an inverter so I can set the interrupt on LOW, but have the pin go LOW when the Echo pin goes HIGH. +Home DIY Electronics has a good article on interrupts and the HC-SR04.

Since the sensor is ranging constantly, it wakes up pretty quickly. If I try to put it in power down mode, it does not wake up (maybe because the sensor shuts down?):  The LED indicating sleep stays on and no gesture will wake it up. There are 5 sleep modes and these are only the 2 extremes. I will play with some of the intermediate modes--next year, or the next time I'm playing with interrupts on an AVR board.

Construction

1. Test the mini
   Since I changed boards, I needed to upload the code, wire the circuit on a breadboard, and test. As described above, all was well.
2. Prep the enclosure
   In this design, the speaker and the battery are now inside the enclosure, I only need holes to bring in wires from the switch and from the HC-SR04. I also drilled 7 holes to let the sound out, places where I planned to put the speaker.
3. Design the board layout
   I needed to mount the Pro Mini, then find room for the amplifier and Micro SD Reader.  This required some planning, so I simulated with header pins on the PCB and marked where I would place the components.  All the components had male headers attached, because I originally set set this up for a breadboard, so I soldered the headers to the printed side of the board.
4. Wire the busses
   I created power and ground busses on the inside edge of the board, next to the battery, using tinned copper bus wire. The board has pairs of adjacent rows of connected holes, so I used two of these pairs (one row for each bus, each adjacent row for connections to the circuit).  The power rail is supplied from the voltage regulator circuit 5V output, and the ground from the 9V battery's negative lead. The positive lead from the battery goes to a 2-wire JST connector, which mates to another connector with leads going to a toggle switch. The other lead from the case (with the + from the battery) is the 9V input to the voltage regulator.
5. Test the Voltage Regulator Circuit
   Since I have habit of messing up connections, and power is a key part of this, I wanted to be sure that I was getting 5V out of this part of the circuit before completing the soldering. When I got it right (after some stupid soldering tricks), I was ready to move on.
6. Mount the components
   All the components had male headers attached, because I originally set set this up for a breadboard, so I soldered the headers to the printed side of the board. I also added an LED and resistor for visual representation of the sleep mode (the code for this was already included, so what the heck).
7. Test the circuit
   Before fastening the circuit board to the enclosure, make sure everything works.  Here's where I ran into trouble.  I worked the continuity function of my multi-meter extensively. I thought I had everything in order, but it failed. I went back to a version of the sketch that had serial commands for testing in it, and saw that the SD board was not initializing.  I rechecked the connections, checked the SD card to see if it could be read, and then got drastic:  clipped the jumpers from the mini to the SD reader, and connected them via alligator leads to another reader.  Still not initializing, so I was pretty sure it was my connections.  One more continuity test revealed a problem with one of the jumpers. I re-soldered, put it back together, and it worked. Stupid soldering tricks, indeed!

   

   Working circuit, mounted. Clockwise from upper left: Adafruit Class D Mono Amp (wires to speaker), voltage regulator circuit, indicator LED and resistor, Pro Mini, Micro SD Card Reader. Yellow and green wires go to HC-SR04, red and black wires on right are power to HC-SR04 (red and black) and from 9V battery and switch (black and gray). 

8. Put it in the box
   See photo at the top of this post.  Enclosing was a matter of adding screws in the prepared holes to secure the PCB, then passing the 4 wires to the HC-SR04 through one hole and the battery connection through another, position the speaker under the holes, and closing the box.
   
9. Video
   Available on Youtube (my channel)