Tuesday, August 30, 2016

Hopping Robot: How I made one


I found this very interesting video, and I will give the author +sauravchakra all the credit for the idea and the demonstration.

However, I would not call this a tutorial--it's a 4+ minute demo of the operation some information on the process. So, I decided to take it to he next step. First, here's all of what I used in the project. Others may add their own ideas, but this is a start, and more than was in the video.

See notes under "Step 5 -Hop!" for planned improvements.

Parts

aluminum: 2 pieces 3cmX1cm (I used scrap from a discarded light fixture)  Author says to drill a 2mm hole 5mm from edge. Since I used bigger screws, I used a 1/8" drill bit (~3mm)
batteries:  3 AAA
battery holder: 3XAAA; see Radio Shack (See note under step 5)
carriage bolt: 1 2" bolt--got it a local hardware store
DC Gear Motor: Only spec is 100RPM. It's a 90 degree shaft,
and we can intuit 4.5V from the power used.  See Jameco
I found one on Amazon for less but shipping takes over a month.
metal rod: 1" long, diameter small enought to fit the wheel, below.
I used parts from a printer tear-down.
plastic: you'll need to cut a piece 5" X 1". I had these around from Amazon.
plastic wheel : 1, small enough to fit in plastic and be held by metal rod above; I used parts from printer teardown, author used a bead
PVC pipe:  need 1 piece 1/2" wide.  Tutorial says 7 cm pipe = ~2.75in--I used 3.5in (outside dimension), from scrap.  Find it at a local hardware store or Home Depot
screws/nuts: author calls for tiny metric screws (like M1.5). I tried that, and my fingers are to fat and clumsy to get that done. I used some 1/2" 4-40 machine screws and nuts that I had bought from a local hardware store
slide switch  (SPDT):  This could be SPST, but this is what author used and also what I had, from Adafruit

Tools and Supplies

Coping Saw: to cut plastic, bought at local hardware store
Files: for deburring metal and plastic--I have this set from Harbor Freight
Hack Saw: for cutting metal and PVC, sourced locally
Heat Gun: to soften plastic for bending and for heat shrink;  inexpensive at Harbor Freight
Heat Shrink Tubing: to insulate soldered wires (batteries/motor/switch), from Radio Shack, Adafruit, et al.
Hot Glue Gun: to attach various components; Home Depot has this one
Snips: to trim metal and plastic--sourced locally
Soldering Tools:solder battery/motor/switch connections, from Radio Shack, Adafruit, et al.
Vise: I make great use of my bench vise like this Craftsman
Wire Strippers: for cutting and stripping the motor and battery wires to prepare for soldering--sourced locally

Assembly

The photo above shows the parts ready for assembly.  Clockwise from upper left:
  1. Slide switch
  2. 2" carriage bolt
  3. DC Gear Motor with aluminum pieces attached to rotating arms
  4. 2 halves of a 1/2" slice of PVC pipe, for the legs
  5. battery holder
  6. piece of ABS plastic, cut to size, bent at the 1/4 with indentation for the wheel, 1/16" holes for the switch leads, and a 1/8" hole for the battery wires
  7. I left the rod and wheel out of the photo. See Step 2.
The process

Step 1 - fabricate the parts
The PVC pipe, the plastic, and the aluminum pieces all needed to be cut out.  
PVC: I found a piece of 3.5" PVC pipe, cut off a half inch slice, then cut that in half
Plastic:  a had some sheets of 1/8" thick ABS, and in fact had plenty of scrap from other projects, so I took a small piece and cut it to size with a coping saw. Then I measured one quarter of the length, drew a line, hit that area with the heat gun, then put it in the vise and bent it to a 90 degree angle. Then I cut out about a 3/4" section, 3/8" high out of the bottom of the bent section.  That's where the wheel will go. I needed a hole for the battery wires and 3 hole for the switch pins, so I drilled those.
Aluminum: I had replaced a failed under-counter fluorescent light fixture and kept the old housing for scrap.  I cut out two 3cm by 1cm pieces (really about 1.25" X .5" ). I tried the small M1.5 screws but my fingers just would not cooperate, so instead of a 2cm hole I drilled a 1/8" hole to accommodate 4-40 machine screws.

legs hot glued to aluminum
Step 2 - attach the legs
one leg with hot glue treads
  1. Drill 1/8" holes in the rotating arms of the motor (make sure you put them on the same side so the metal pieces are oriented in the same direction--i.e., not one horizontal and the other vertical). My drill doesn't do metal too well, so I used a hammer and nail to complete the hole
  2. Fasten the aluminum pieces to the arms with 3/8" 4-40 screws and nuts
  3. Hot glue the PVC pieces, with the convex side facing the rear (opposite from the rotating end).
  4. Add lines of hot glue about every 1/2" along the outside of the PVC for traction.
Step3 - populate the frame
rod, wheel, and slot in frame
wheel hot glued to frame













  1. Put the rod through the wheel and hot glue it to the open area in the frame (making sure that the wheel clears the bottom of the frame and turns freely)
  2. Hot glue the switch to the frame, with the pins through the 3 holes
  3. Hot glue the battery holder to the frame and thread the wires through the 1/8" hole
  4. Hot glue the motor+legs to the frame--check the photos to be sure everything is facing in the right direction
Step4 - wire it up
  1. First connect the red wires and black wires from the motor and batteries to each other.  The legs should turn clockwise. If not, reverse the wires.
  2. With the polarity verified, start trimming and soldering.
  3. After wiring and testing, hot glue the 2" carriage bolt in place for stability




Step 5 - Hop!

It's done and it works, but I need to make some improvements.

  1. I couldn't find my hot glue gun, so I borrowed a low-temp one from my wife.  I'm blaming that for the fact that the legs come off at times, so I'm going to find mine or by a real one, and re-fasten the legs
  2. The open battery holder does not secure the batteries and the tend to fall out.  I have enclosed ones on order from eBay, but ti will take a while
  3. The PVC may be too heavy, because the legs what to stay still while the motor spins.  It's still amusing, but not as designed.  I may try thinner legs (e,g., 3/8" slices of PVC instead of 1/2")

Monday, August 22, 2016

Interference Problem Solved

For the category "better late than never"...

Before I left for Texas for a month, I disconnected the antenna cables to my Ten Tec Jupiter HF  rig and my Yaesu FT1900R 2 meter rig.  When I got back and reconnected everything,  I had major QRN on 2 meters. People could hear me fine, but reception was spotty at best.  

I tried moving the cable around with no success.  The only difference from before the trip is that central air conditioning unit was on.  I never got motivated to get into into in detail, because HF was fine (I thought) and I use 2 meters more for mobile.

This past weekend we had an ARES drill for which I was assigned to operate my base station. I turned off the A/C--no difference on 2M.  The next suspect was the computer, but that's always been right where it is.  I shut the computer down and the static disappeared. I looked online and found that the monitor may be the problem.  I tried just turning off the monitor without shutting down--that was it.  Brain jock that I am, I ran the antenna cable behind the monitor.  I moved it, running it under my desk to the Yaesu, and that was it.

We were also operating on 40 meters.  I was getting static there in about a 3kHz range. Since the radio gods have a sense of humor, the frequency we used was right in the middle of that range.  It turns out that the source was the A/C--when the unit switched on, I got static.

Moral of the story: don't run antenna cables behind a computer monitor, and A/C has potential  to produce interference.

Monday, August 15, 2016

Control AC Devices over the Internet



When I built the project described in my post on controlling devices from a smartphone, my brother-in-law said "yeah, but can you do that over the internet?"  The answer was yes, but I needed to wait until my +Adafruit Industries Feather Huzzah with ESP8266 WiFi arrived. I had already decided to use adafruit.io as the browser component.  It was super easy to set up a dashboard and two feeds-a button interface to turn the light on and off and a text feed (output from the Huzzah) so I could see what the code thinks it's doing (see the tutorials at the adafruit.io link provided above.

By following the tutorials and code examples, and cloning what I could from tmy bluetooth project (see above), I got it working very quickly.  However, I wanted it to be a useful device that I could give to my brother-in-law. As noted in other posts, he has helped with all kinds of projects.  So, I needed a project box, a circuit board and a few other things, and I needed to do some designing. My first thought was to find a 120V relay and make my own Power Switch Tail.  In studying the schematic, I found that there were all kinds of circuit protections included, so I decided to go with a commercial product.  The powerswitch was US$26, so I looked for an alternative.  I found this AC/DC Control Relay on Amazon. The price has gone up by $2 since I bought it, but it's still $9 less than the powerswitch and has more capability. For example, it has 4 receptacles, 2 normally off and 2 normally on, so it can control multiple devices.

Parts and supplies list, partially annotated

  • AC/DC Comtrol Relay (takes input from the Huzzah: a signal line and a ground line; different from powerswitch tail, which also takes a DC power input; in addition the logic is opposite--power swith tail closes the relay on LOW, this one closes it on HIGH) )
  • +Adafruit Industries Feather Huzzah with ESP8266 WiFi Board
  • 2-wire JST connectors (connect to the relay)
  • LEDs (I used 5mm, one green, one red)
  • resistors (current-limiting for LEDs--I used 330Ohm)
  • 22-gauge solid core hookup wire 
  • tinned copper bus wire
  • project box (this was tight, but I wanted it small)
  • circuit board (I started to use plain perf board, but it broke--these boards were not quite the right size, so I had to file them. The soldering pads were useful.)
  • 3/8" 4-40 machine screws (to attache the circuit board to the standoffs in the box)
  • Drill and bits
  • A set of files (to deburr the drilled holes, and to size the holes properly)
  • Normal project tools: soldering iron and accessories, multimeter, strippers, clippers, helping hands and/or Panavise Jr., and the like
  • Super Glue or the like to fix the LEDs and JST to the box
  • Heat shrink tubing

Concept

The circuit is very simple, maybe deceptively so.  As you will see in the code, it connects to wifi, then connects to adafruit.io, and turns everything off at the start (in setup), then waits for orders from adafruit.io.  The toggle button on the adafruit.io dashboard sends info to the Huzzah, and depending on the state of the lamp (or whatever device you have plugged into the relay), it toggles the state.

The LEDs are used as indicators.  The green LED turns on after successful connection to adafruit.io (if it's not on, there's a problem). The red LED turns on and off with the lamp or other device (also to help see what's going on).

Schematic


Assembly

I spent a lot of time planning where to put the LEDS and the JST connectot. I had some scrap ABS plastic left from my robot cart project, so I used that to test a few options:




I wanted the JST to be recessed, but that didn't work out. I liked the LED holders, but they took up too much room in the box.

I drilled a hole in one end of the box for the USB cable, then drilled 3 3/16" holes in one side for the LEDs and JST connector.  The holes needed to be enlarged, so I took time to get just enough room to get the components through, while still not allowing the whole component to pass.

I had to expand two of the mounting holes on the circuit board to get the screws through. The other two holes did not line up with the standoffs.  I planned to mount the board with the soldering pads down, so I could keep the minimal wiring out of the way.

I positioned the Huzzah on the board, and used hookup wire to fix the back end to the circuit board through the mounting holes.  I had to remove one later to allow access to one of the LED holes in the case.  I ran black hookup wire under the board from the HUZZAH GND pin to the Ground bus on the other side of the board.  I soldered the hookup wire to the GND pin and to the soldering pad in the corner of the opposite side.  I ran tinned copper bus wire from the hookup wire down that side of the board and soldered each corner.


Next, I conencted the 330Ohm resistors through the board to the Ground bus and soldered them to it, then cut the wires on the female end of the JST to length, positioned it in the hole in the box, and soldered the black wire to the Ground bus and the red wire to pin 2 (see schematic above).

Note: if I were to do this again, I would run the Ground bus down the opposite side of the board, solder one end of the resistors to it on the underside, and solder the other ends of the resistors to the ground leads of the LEDs. That would make it neater.

I then took the time to test the circuit to be sure the connections were OK.  Using the Arduino IDE serial monitor and the relay with a lamp plugged in, I found that all was good.  I then added the LEDs, connecting the proper leads to the resistors and to the correct pins, and soldering.  One more test showed the LEDs functioning properly, so I screwed the circuit board to the box.

The final touches were to trim the connections to the resistors, use some electrical tape for insulation, and to super glue the LEDs and JST connector to the box.  Finally, I spliced the male end of the JST to hookup wires leading to the corresponding connections on the relay (there is a terminal block on the relay).  After testing the connections for continuity with my multimeter, I applied heat shrink to each splice and then a long piece of heat shrink to the whole connection.
Enclosure before gluing LEDS and JST and adding screws

Project Video

On my youtube channel

Code

/***************************************************
  Adafruit MQTT Library ESP8266 Example

  Must use ESP8266 Arduino from:
    https://github.com/esp8266/Arduino

  Works great with Adafruit's Huzzah ESP board:
  ----> https://www.adafruit.com/product/2471
  products from Adafruit!

  Written by Tony DiCola for Adafruit Industries.
  Adafruit IO example additions by Todd Treece.
  MIT license, all text above must be included in any redistribution
 ****************************************************/
/*  Adafruit invests time and resources providing this open source code,
  please support Adafruit and open-source hardware by purchasing */

/*2015-08-15 Virgil Machine
  Light goes on, light goes off, internet style
  I used the adfruit.io tutorial and the adafruit esp8266
  tutorial and library examples to get the connection stuff.
  The logic is mainly cloned from my bluetooth example 
  (see virgilmachine.blogspot.com). Connects to WIFI, connects 
  to adafruit.io, turns on green LED to indicate connection,inbitializes 
  logic and devices to off, then waits for instructions from 
  adafruit.io--toggle switch to turn light on and off. Sets relay
  pin to HIGH, also turns on red LED and on-board LED, and vice versa.
  */
#include
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"

// function prototypes
void connect(void);

/****************************** Pins ******************************************/

#define LAMP           2  // AC/DC Control Relay 
#define LED            0  // on-board LED
#define POWER_LED      4  // lED to show power on
#define LAMP_LED       5  // lED to show LAMP on

/************************* WiFi Access Point *********************************/
//use your own values here

#define WLAN_SSID       "SSID"
#define WLAN_PASS       "PASSWORD"

/************************* Adafruit.io Setup *********************************/

#define AIO_SERVER      "io.adafruit.com"
#define AIO_SERVERPORT  1883
//use your own values here
#define AIO_USERNAME    "USERNAME"
#define AIO_KEY         "adafruit.io KEY"

/************ Global State (you don't need to change this!) ******************/

// Create an ESP8266 WiFiClient class to connect to the MQTT server.
WiFiClient client;

// Store the MQTT server, client ID, username, and password in flash memory.
// This is required for using the Adafruit MQTT library.
const char MQTT_SERVER[] PROGMEM    = AIO_SERVER;
// Set a unique MQTT client ID using the AIO key + the date and time the sketch
// was compiled (so this should be unique across multiple devices for a user,
// alternatively you can manually set this to a GUID or other random value).
const char MQTT_CLIENTID[] PROGMEM  = __TIME__ AIO_USERNAME;
const char MQTT_USERNAME[] PROGMEM  = AIO_USERNAME;
const char MQTT_PASSWORD[] PROGMEM  = AIO_KEY;
int current = 0;
char light_on[] = "Light Goes On";
char light_off[] = "Light Goes Off";
//2016-08-08 vm char stuff replaced by boolean
bool lamp_on = false;  //initalized to off to match the rest of the code

// Setup the MQTT client class by passing in the WiFi client and MQTT server and login details.
Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, AIO_SERVERPORT, MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD);

/****************************** Feeds ***************************************/

// Setup a feed called 'lamp' for subscribing to changes.
// Notice MQTT paths for AIO follow the form: /feeds/
const char LAMP_FEED[] PROGMEM = AIO_USERNAME "/feeds/UncleJimThing";
Adafruit_MQTT_Subscribe lamp = Adafruit_MQTT_Subscribe(&mqtt, LAMP_FEED);
// Use feed UncleJimText as TEXT_FEED for publishing changes.
// Notice MQTT paths for AIO follow the form: /feeds/
const char TEXT_FEED[] PROGMEM = AIO_USERNAME "/feeds/UncleJimText";
Adafruit_MQTT_Publish text = Adafruit_MQTT_Publish(&mqtt, TEXT_FEED);
/*************************** Sketch Code ************************************/

void setup() {

  // setup relay and LED pins as outputs and start off as LOW
  pinMode(LAMP, OUTPUT);
  digitalWrite(LAMP, LOW);  //default to off at startup (had this backwards) 
  pinMode(LED, OUTPUT);  //for testing
  digitalWrite(LED, LOW);  //default to off at startup
  // setup pins for indicator LEDS 
  pinMode(LAMP_LED, OUTPUT);
  digitalWrite(LAMP_LED, LOW);  //default to off at startup
  // POWER_LED IS SET to HIGH in connect() routine, after successful connection
  //but default to off until then
  pinMode(POWER_LED, OUTPUT);  //to show if we're connected
  digitalWrite(POWER_LED, LOW);  //default to off at startup 
  
  Serial.begin(115200);

  Serial.println(F("Uncle Jim IO Example"));

  // Connect to WiFi access point.
  Serial.println(); Serial.println();
  delay(10);
  Serial.print(F("Connecting to "));
  Serial.println(WLAN_SSID);

  WiFi.begin(WLAN_SSID, WLAN_PASS);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(F("."));
  }
  Serial.println();

  Serial.println(F("WiFi connected"));
  Serial.println(F("IP address: "));
  Serial.println(WiFi.localIP());

  // listen for events on the lamp feed
  mqtt.subscribe(&lamp);

  // connect to adafruit io
  /* when we connect successfully, the LED is turned on
  so we enter loop with the POWER_LED indicator on
  but it's off until then
  */
  connect();
/****2016-07-17 VM 
     We want the test to say "light goes off at startup, since we set if off in setup
     I think this will work here--***experiment***
****/
     text.publish(light_off);
}

void loop() {

  Adafruit_MQTT_Subscribe *subscription;

  // ping adafruit io a few times to make sure we remain connected
  if(! mqtt.ping(3)) {
    // reconnect to adafruit io
    if(! mqtt.connected())
    { digitalWrite(POWER_LED, LOW);  //turn off LED to show we're not connected  
      connect();
    }  
  }


  // this is our 'wait for incoming subscription packets' busy subloop
  while (subscription = mqtt.readSubscription(1000)) {

    // we only care about the lamp events
    if (subscription == &lamp) {

      // convert mqtt ascii payload to int
      char *value = (char *)lamp.lastread;
      Serial.print(F("Received: "));
      Serial.println(value);
      Serial.print(F("\nlamp-state in: "));
      Serial.println(lamp_on);
      int current = atoi(value);
      if (lamp_on) {  
        Serial.println(light_off);
        text.publish(light_off);
        digitalWrite(LAMP, LOW);  //RELAY
        digitalWrite(LED, LOW);  //ON-BOARD
        digitalWrite(LAMP_LED, LOW); //INDICATOR
      } else {  
        Serial.println(light_on);
        text.publish(light_on);
        digitalWrite(LAMP, HIGH); 
        digitalWrite(LED, HIGH);
        digitalWrite(LAMP_LED, HIGH);          
      } 
      lamp_on = !lamp_on; //toggle lamp state         
      Serial.print(F("\nlamp-state out: "));
      Serial.println(lamp_on);
  
      Serial.print(F("\nSending button value: "));
      Serial.print(value);
      Serial.print("... ");

    }   //if subscription is lamp
  }     //while subscription
}       //loop

// connect to adafruit io via MQTT
void connect() {

  Serial.print(F("Connecting to Uncle Jim IO... "));

  int8_t ret;

  while ((ret = mqtt.connect()) != 0) {

    switch (ret) {
      case 1: Serial.println(F("Wrong protocol")); break;
      case 2: Serial.println(F("ID rejected")); break;
      case 3: Serial.println(F("Server unavail")); break;
      case 4: Serial.println(F("Bad user/pass")); break;
      case 5: Serial.println(F("Not authed")); break;
      case 6: Serial.println(F("Failed to subscribe")); break;
      default: Serial.println(F("Connection failed")); break;
    }

    if(ret >= 0)
      mqtt.disconnect();

    Serial.println(F("Retrying connection..."));
    delay(5000);

  }

  Serial.println(F("Uncle Jim IO Connected!"));
  digitalWrite(POWER_LED, HIGH);  //turn on LED to show we're connected  
}

Saturday, May 28, 2016

Control AC devices with a Smartphone

I found this tutorial and thought it was a cool idea. It describes how to control a light (or any AC device) from a Bluetooth app on a smartphone.

I thought it would be something that my granddaughter would enjoy when she comes this summer. The tutorial gives what I assume is a lot of useful information, but it gets into the weeds of bluetooth much more than I'm interested in at this point, and all I want is to allow a 6-year-old to turn a light on and off.

I followed the tutorial though steps 1 and 2.  Step one uses Blink to flash an LED. Step two adds a button with some interrupt handling. The authors do not mention that in order to get this code to work without a bluetooth nRF8001 module connected, you need to comment out the line "blePeripheral.begin();" in setup--otherwise it hangs there--I guess waiting for a bluetooth board. So I got steps 1 and 2 working.

For step 3, I need to add a board. I have the +Adafruit Industries Bluetooth LE module  (nRF8001 chip) that the authors suggest, but I found it simpler to use the Adafruit Feather Bluefruit LE board (nRF51822 chip) . Since the boards use different Nordic chips, I had to figure out how to get the code to work. The Make tutorial uses the BLEPeripheral library, which I did not get to work, so I used the Adafruit_BluefruitLE_nRF51 library, and the functions are very different.

The code in the Make tutorial looked overly complex for what I wanted,  Since this is my first Bluetooth project, so I wanted to start slowly.  Following the Adafruit tutorial, I installed the " Adafruit_BluefruitLE_nRF51" library and the Adafruit BLE connect app for Android and started working through the example programs. "bleuart_cmdmode" did what I needed: communicate between the module and the app. I set it up so that sending "ON"--all caps--turns the light on and "OFF"--caps again--turns it off,

With nothing but the Feather, a resistor, and an LED I was able to turn the LED on and off from my phone. After 40 years of programming I still get a kick out of seeing something work the first time--no matter how simple.

Next I needed to add the PowerSwitch Tail. It was very simple, except that I did not have a screwdriver small enough to tighten the terminal blocks. Fortunately, my brother-in-law has tools (in addition to skills) and we got it connected. I connected pin 1 to the 3.3V rail on the breadboard, pin 2 to pin 6 on the Feather (the LED pin), and pin 3 to the ground rail on the breadboard.  Then I plugged one end of the PowerSwitch to a 110VAC wall receptacle and plugged a light into the other end.

Power Switch Tail with jumper wires, ready for hookup
The PowerSwitch is a Normally Open relay, so when you hook it up the device (light in my case) is off.  When pin 2 on the PowerSwitch is set LOW, the relay closes and the device turns on.  This is the reverse of the way my code worked, so when the LED was on (Feather pin 6 HIGH), the light was off and vice versa.  This makes a little sense--it gives you some light when the AC light is off, but it's not intuitive for a 6-year-old to say "ON"and turn a light off.  So, I added a pin (5), connected pin 2 of the PowerSwitch to that, and set it LOW for ON and HIGH for OFF.

Project Video.

Now that I feel comfortable with the concepts (as far as I've gone), I can go back to the original Make tutorial and learn more. This is cool.

Here's the code that goes with the video (as mentioned above it's a modification of the "bleuart_cmdmode" example in the Adafruit Bluefruit nRF51 library):

/*********************************************************************
 This is an example for our nRF51822 based Bluefruit LE modules

 Pick one up today in the adafruit shop!

 Adafruit invests time and resources providing this open source code,
 please support Adafruit and open-source hardware by purchasing
 products from Adafruit!

 MIT license, check LICENSE for more information
 All text above, and the splash screen below must be included in
 any redistribution
*********************************************************************/

#include
#include
#if not defined (_VARIANT_ARDUINO_DUE_X_) && not defined (_VARIANT_ARDUINO_ZERO_)
  #include
#endif

#include "Adafruit_BLE.h"
#include "Adafruit_BluefruitLE_SPI.h"
#include "Adafruit_BluefruitLE_UART.h"

#include "BluefruitConfig.h"

/*=========================================================================
    APPLICATION SETTINGS

    FACTORYRESET_ENABLE       Perform a factory reset when running this sketch
   
                              Enabling this will put your Bluefruit LE module
                              in a 'known good' state and clear any config
                              data set in previous sketches or projects, so
                              running this at least once is a good idea.
   
                              When deploying your project, however, you will
                              want to disable factory reset by setting this
                              value to 0.  If you are making changes to your
                              Bluefruit LE device via AT commands, and those
                              changes aren't persisting across resets, this
                              is the reason why.  Factory reset will erase
                              the non-volatile memory where config data is
                              stored, setting it back to factory default
                              values.
       
                              Some sketches that require you to bond to a
                              central device (HID mouse, keyboard, etc.)
                              won't work at all with this feature enabled
                              since the factory reset will clear all of the
                              bonding data stored on the chip, meaning the
                              central device won't be able to reconnect.
    MINIMUM_FIRMWARE_VERSION  Minimum firmware version to have some new features
    MODE_LED_BEHAVIOUR        LED activity, valid options are
                              "DISABLE" or "MODE" or "BLEUART" or
                              "HWUART"  or "SPI"  or "MANUAL"
    -----------------------------------------------------------------------*/
    #define FACTORYRESET_ENABLE         1
    #define MINIMUM_FIRMWARE_VERSION    "0.6.6"
//    #define MODE_LED_BEHAVIOUR          "MODE"
    #define MODE_LED_BEHAVIOUR          "MANUAL" //2016-05-27 vm
    #define TAIL_PIN                    5
    #define LED_PIN                     6
    int LED_STATE;
    char* x;
    char y;
/*=========================================================================*/

// Create the bluefruit object, either software serial...uncomment these lines
/*
SoftwareSerial bluefruitSS = SoftwareSerial(BLUEFRUIT_SWUART_TXD_PIN, BLUEFRUIT_SWUART_RXD_PIN);

Adafruit_BluefruitLE_UART ble(bluefruitSS, BLUEFRUIT_UART_MODE_PIN,
                      BLUEFRUIT_UART_CTS_PIN, BLUEFRUIT_UART_RTS_PIN);
*/

/* ...or hardware serial, which does not need the RTS/CTS pins. Uncomment this line */
// Adafruit_BluefruitLE_UART ble(Serial1, BLUEFRUIT_UART_MODE_PIN);

/* ...hardware SPI, using SCK/MOSI/MISO hardware SPI pins and then user selected CS/IRQ/RST */
Adafruit_BluefruitLE_SPI ble(BLUEFRUIT_SPI_CS, BLUEFRUIT_SPI_IRQ, BLUEFRUIT_SPI_RST);

/* ...software SPI, using SCK/MOSI/MISO user-defined SPI pins and then user selected CS/IRQ/RST */
//Adafruit_BluefruitLE_SPI ble(BLUEFRUIT_SPI_SCK, BLUEFRUIT_SPI_MISO,
//                             BLUEFRUIT_SPI_MOSI, BLUEFRUIT_SPI_CS,
//                             BLUEFRUIT_SPI_IRQ, BLUEFRUIT_SPI_RST);


// A small helper
void error(const __FlashStringHelper*err) {
  Serial.println(err);
  while (1);
}

/**************************************************************************/
/*!
    @brief  Sets up the HW an the BLE module (this function is called
            automatically on startup)
*/
/**************************************************************************/
void setup(void)
{
//2016-05-27 define light pins as output and set them to off
//(relay on switch tail is reverse--flops closed for on when low)
  pinMode(LED_PIN, OUTPUT);
  pinMode(TAIL_PIN, OUTPUT);
  digitalWrite(LED_PIN, LOW);
  digitalWrite(TAIL_PIN, HIGH);
  LED_STATE = 0;
//  while (!Serial);  // required for Flora & Micro--2016-05-28 vm causes feather to hang if not
//  connected via usb
//2016-05-27 end
delay(500);

  Serial.begin(115200);
  Serial.println(F("Adafruit Bluefruit Command Mode Example"));
  Serial.println(F("---------------------------------------"));

  /* Initialise the module */
  Serial.print(F("Initialising the Bluefruit LE module: "));

  if ( !ble.begin(VERBOSE_MODE) )
  {
    error(F("Couldn't find Bluefruit, make sure it's in CoMmanD mode & check wiring?"));
  }
  Serial.println( F("OK!") );

  if ( FACTORYRESET_ENABLE )
  {
    /* Perform a factory reset to make sure everything is in a known state */
    Serial.println(F("Performing a factory reset: "));
    if ( ! ble.factoryReset() ){
      error(F("Couldn't factory reset"));
    }
  }

  /* Disable command echo from Bluefruit */
  ble.echo(false);

  Serial.println("Requesting Bluefruit info:");
  /* Print Bluefruit information */
  ble.info();

  Serial.println(F("Please use Adafruit Bluefruit LE app to connect in UART mode"));
  Serial.println(F("Then Enter characters to send to Bluefruit"));
  Serial.println();

  ble.verbose(false);  // debug info is a little annoying after this point!

  /* Wait for connection */
  while (! ble.isConnected()) {
      delay(500);
  }
//Serial.println(
  // LED Activity command is only supported from 0.6.6
//  if ( ble.isVersionAtLeast(MINIMUM_FIRMWARE_VERSION) )
//  {
    // Change Mode LED Activity
    Serial.println(F("******************************"));
    Serial.println(F("Change LED activity to " MODE_LED_BEHAVIOUR));
    ble.sendCommandCheckOK("AT+HWModeLED=" MODE_LED_BEHAVIOUR);
    Serial.println(F("******************************"));
//  }
}

/**************************************************************************/
/*!
    @brief  Constantly poll for new command or response data
*/
/**************************************************************************/
void loop(void)
{
  // Check for user input
  char inputs[BUFSIZE+1];

  if ( getUserInput(inputs, BUFSIZE) )
  {
    // Send characters to Bluefruit
    Serial.print("[Send] ");
    Serial.println(inputs);

    ble.print("AT+BLEUARTTX=");
    ble.println(inputs);

    // check response stastus
    if (! ble.waitForOK() ) {
      Serial.println(F("Failed to send?"));
    }
  }

  // Check for incoming characters from Bluefruit
  ble.println("AT+BLEUARTRX");
  ble.readline();
  if (strcmp(ble.buffer, "OK") == 0) {
    // no data
    return;
  }
  // Some data was found, its in the buffer
  Serial.print(F("[Recv] ")); Serial.println(ble.buffer);
//2016-05-27 vm test buffer for ON or OFF, display results  on serial monitor and bluetooth device,
//turn LED and Light on or off (or do nothing)
  if (strcmp(ble.buffer,"ON")== 0) {
      Serial.println("Light ON");
      ble.print("AT+BLEUARTTX=");
      ble.println("Light ON");
      digitalWrite(LED_PIN, HIGH);
      digitalWrite(TAIL_PIN, LOW); //relay logic is reverse of LED
  } else if (strcmp(ble.buffer,"OFF")== 0) {
      Serial.println("Light OFF");
      ble.print("AT+BLEUARTTX=");
      ble.println("Light OFF");
      digitalWrite(LED_PIN, LOW);
      digitalWrite(TAIL_PIN, HIGH);    //relay logic is reverse of LED
  } else {
      Serial.println("Light not changed");
      ble.print("AT+BLEUARTTX=");
      ble.println("Light not changed");
  }
  ble.waitForOK();
}

/**************************************************************************/
/*!
    @brief  Checks for user input (via the Serial Monitor)
*/
/**************************************************************************/
bool getUserInput(char buffer[], uint8_t maxSize)
{
  // timeout in 100 milliseconds
  TimeoutTimer timeout(100);

  memset(buffer, 0, maxSize);
  while( (!Serial.available()) && !timeout.expired() ) { delay(1); }

  if ( timeout.expired() ) return false;

  delay(2);
  uint8_t count=0;
  do
  {
    count += Serial.readBytes(buffer+count, maxSize);
    delay(2);
  } while( (count < maxSize) && (Serial.available()) );

  return true;
}

Monday, April 25, 2016

On the air!

As described in  this post  the antenna (G5RV Jr) was mounted yesterday. Today, we finished the connections (see photo), and hooked up the Ten Tec Jupiter.
Ladder line connected to coax via a juntion box, to the balun and off to the rig
I was able to hear a lot on 20 meters and some on 40.  It's tough to break in at times, and it's not always clear whether I'm not getting through or some one else is transmitting over me. Very often, you only hear one side of a conversation.  For example, I could hear someone in the Czech Republic clearly. At one point he was talking to someone in Connecticut, probably 200-300 miles from hear, but I could not here the Connecticut station.  Propagation is funny like that.

I did check into a marine net just to be sure I was getting out, and a relay station in Georgia confirmed the check-in. Later I spoke with someone in Portugal and someone else in Nicaragua.  This is cool. Tommorow morning I'll try ECARS (East Coast Amateur Radio Service) to see how I do on 40 meters.

Sunday, April 24, 2016

G5RV Jr mounted--almost all set


On the house (middle)--J-Pole for 2 meters on the left
G5RV Jr on the mast with balun and juntion box
I wanted to get my new antenna mounted and installed yesterday (23 April) so I could get on the air for Marconi Day.  Unfortunately, it rained and we decided to be safe.


Today, we go the antenna mounted on the house and ran the horizontal wires out to trees, The job went smoothly almost without issue.  The only problem was that the ladder line extended down farther than I expected. We measured, and it was 19+ft.  I went back and checked the specs, which say 16ft. I went to my 2 meter rig and raised a local ham with the same antenna, and he verified the 16ft. 

So, we took the antenna down, cut the ladder line down, desoldered the existing connection from ladder line to the SO-239, and soldered the shorter piece. Then we re-mounted the antenna and ran the horizontals out to trees in the back yard. We used ropes connected to the insulators to secure the antenna to the trees, and inserted 24" rubber bungees for strain relief.

By that time we were ready to call it a day.  For tomorrow:

  1. mount the choke balun on then house
  2. mount a waterproof juntion box next to the balun
  3. connect the balun to the ladder line inside the junction box
  4. connect coax to the balun, with a lightning arrestor  between them
  5. ground the lightning arrestor to the ground rod
  6. run the coax through the wall to the shack and connect to the HF rig
  7. figure out what I need to do for station ground
  8. get on the air!

Saturday, April 9, 2016

@MAKE: Electronics Experiment 34 started

As I mentioned in this post, I became discouraged by the need for a $20 cable to program a $3 microcontroller, particularly since Charles did not mention it it the parts list or supplies.  Also, Charles dismissed the less expensive option of using a computer's serial port.  I submitted an erratum to the publishers on this--since the book's subtitle is "Learning by Discovery" and it's a +Make: book, I though it would be more in the spirit of the book to lead the reader to discover and make. I love the book and it has provided me with great deal of learning and satisfaction, but I found this irritating.  I got over it, and now I'm on to the project.

Also, I have not found any posts or videos of these experiments, so I might as well do it.

But first, I needed a serial port. Most late-model computers do not have the old-fashioned 9-pin RS232 ports for what is normally called a DB9 connector but really is DE9. Fortunately, I hoard old computers and have a 14-year old Windows XP computer with serial ports on the motherboard.  If there had been on a PCI card rather than the motherboard, I could have swapped that out  into my regular desktop.  That left me with 2 choices:  fire up the XP machine and use that to program the PICAXE, or buy a PCI card for my desktop. Since I doing this because I'm cheap, I chose the former. PCI cards cost US$7 and up from Amazon, Newegg, and the like, and as low as $4 on eBay. If I decide to use the PICAXE for more than this project, that's an option.

The XP machine started up fine, and I was able to download and install the PICAXE software according to the book instructions (or see the PICAXE web site).  I still needed a cable.  Here again, I had two options:
1. find a serial to something cable, cut it, figure out which wires go to which pin, and connect the 3 wires I need to the PICAXE
2. make my own
Again, this is a makers' book, so I decided to make one.  A quick Google yielded this set of instructions. I bought a DB9F (as in female) connector from Amazon. Following the aforementioned instructions, I soldered 24" solid core wires to the pins I needed:
red wire to pin 2       (Rx--receive--computer in)
green wire to pin 3   (Tx--transmit--computer out) I didn't have white solid core wire
black wire to pin 5   (Ground)
I heatshrinked the connections for insulation.
I then cut a servo wire in half and kept the half with the end that I could connect to a 3-pin header on the breadboard and:

  1. slid small heatshrink on each lead
  2. slid larger heatshrink over the 3 wires to the DB9
  3. spliced the servo wires to the connector wires with solder, matching the wires by color (red/red/ black/ black, white/green) 
  4. heatshrinked the splices
  5. heatshrinked the cable
  6. snapped the cover on the serial connector end
Viola, I had a cable.  Here are some photos of the process.
Tools and supplies ready 
to make the PICAXE cable
DB9F ready to solder

soldered wires ready for heatshrink
finished cable


Next step:  configure the breadboard:
  1. add a 2.1mm barrel jack to bring unregulated 9V to the breadboard via wall wart or 9V battery
  2. add a voltage regulator circuit to deliver clean 5V to the power rails on each side of the breadboard
    .  the circuit consists of 2 100uf capacitors, 2 .1uf capacitors, and an LM7805 voltage regulator
    .  Charles' instructions are good, see schematic
  3. add the PICAXE to the breadboard and connect it to power and to the computer serial output
    .  I have a PICAXE 08M2, pin 2 is serial in and pin 7 is serial out, so the red wire (computer out) goes to pin 2 (see next bullet), and the white wire (computer in) goes to pin 7 (i,e, computer in to PICAXE out, computer our to PICAXE in)
    .  actually the red wire goes to a breadboard hole in a row between a 10K resistor that goes to a breadboard ground rail and a 22K resistor that goes to PICAXE pin 2--keeping pin 2 pulled to GND when it's not receiving
    .  PICAXE pin 1 goes to a breadboard 5V rail, and pin 8 goes to a breadboard ground rail
  4. Add an LED for testing--connected to PICAXE pin 6 and on to GND through a 330Ohm resistor
Fritzing diagram of circuit--the business on the left is the voltage regulator circuit



I had a heck of a time with the voltage circuit.  I kept getting ~9V out. I tried multiple units, and checked ny wiring.  Finally I set up a circuit like the L7805 datasheet, and it worked--exactly 5V out. I was going to submit another erratum on the book, but as I wrote ti it didn't make sense that I would get 9V out, so I rewired it in a different spot on the breadboard: 4.98V out.  I moved it back to the original location: 9V out.  I'm doing something stupid, but I'm ready to move on to the PICAXE and test my cable, so I'll put it back where it works and declare victory.

breadboarded circuit with messy wires

Now, we're ready to test the cable and circuit.

Oops.  I cannot get the XP machine to recognize the PICAXE./  I have a problem with my cable (although I don't think so, but I'll check), the circuit, my computer, or something else. It could be the breadboard--I suspect that's the problem with the voltage regulator circuit--see above.  I've done some preliminary checking, but I'm not there yet.  The book is absolutely no help on this since Charles went the non-Maker route, I'll do another post if/when I get something working.