Tuesday, December 12, 2017

Ultimate Battery Circuit Design Part 2

In this video series we build the ultimate battery circuit that can handle various battery chemistry's, charge batteries, perform load sharing during charging, handle input voltage levels that are higher or lower than the output, and more. In part 2 we will look at the PCB layout with a focus on the buck boost DC to DC Converter and look at the BOM.







Sunday, December 3, 2017

Ultimate Battery Circuit Design Part 1

In this video series we build the ultimate battery circuit that can handle various battery chemistry's, charge batteries, perform load sharing during charging, handle input voltage levels that are higher or lower than the output, and more. In part 1 we will look at the circuit configuration and component values that we plan to use.






Sunday, November 5, 2017

How to Build a Simple DC Electronic Load with Arduino Part 2

In this video we look at how to make a simple DC electronic load with Arduino and some simple components. In part two 2 we add some flexible measurement capabilities.







//***************************Arduino Code*************************************************
#include <Average.h> /* * This code was used for a tutorial on how to build a simple eload with Arduino * The Tutorial can be found on the ForceTronics YouTube Channel * This code is public domain and free for anybody to use at their own risk */ //Uncomment AVGMEAS to print out avg measurement data and uncomment FASTMEAS to print fast voltage or current measur #define AVGMEAS //#define FASTMEAS //uncomment to print fast current measurements, leave commented to print fast voltage measurements //#define FASTAMP //The following variables set the eload sequence const int sValues[] = {20,50,280}; //set the DAC value for each step const unsigned long sTime[] = {350,50,15}; //set the dwell time for each step const int sNum = 3; //number of steps in the sequence, this number should match the number or items in the arrays long repeat = -1; //set the number of times the sequence repeats, -1 means infinite //The following variables control the measurement rates int measInterval = 5; //in milli seconds, fast measurement rate. This should be less than or equal to measAvgInt int measAvgInt = 1000; //this is done in milliseconds and should be a multiple of the meas interval int aCount = 0; //tracks where we are in the sequence unsigned long sStart; //trcks when a sequence step starts its timer unsigned long mStart; //tracks when a new measurement interval starts unsigned long aHours = 0; //holds amp hour value const unsigned long m2Hours = 360000; //constant value for converting mil sec to hours const float lRes = 5.08; //exact value of eload resistor --> 5.08 const float rMult = 1.51; //multiplier for resistor divider network: R1 = 5.08k and R2 = 9.98k ratio is 9.98 / (9.98 + 5.08) = .663 --> 1.51 const byte aDCVolt = A2; //ADC channel for measuring input voltage const byte aDCCurrent = A4; //ADC channel for measuring voltage across resistor Average<float> voltMeas((measAvgInt/measInterval)); //create average obect to handle voltage measurement data Average<float> currMeas((measAvgInt/measInterval)); //create average object to handle current measurement data void setup() { pinMode(A0, OUTPUT); //A0 DAC pin to output analogWriteResolution(10); //default DAC resolution is 8 bit, swith it to 10 bit (max) analogReadResolution(12); //default ADC resolution is 10 bit, change to 12 bit Serial.begin(57600); analogWrite(A0, sValues[aCount]); //Set DAC value for first step sStart = mStart = millis(); //start timer for seq and measure interval } void loop() { while(repeat > 0 || repeat < 0) { //loop controls how often sequence repeats //timer for changing sequence step if(timer(sTime[aCount],sStart)) { aCount++; //go to next sequence step if(aCount >= sNum) aCount = 0; //if at end go back to beginning analogWrite(A0, sValues[aCount]); //Set DAC value for step sStart = millis(); //reset timer } if(timer(measInterval,mStart)) { voltMeas.push(inputVolt(aDC2Volt(analogRead(aDCVolt)))); //push value into average array currMeas.push(inputCurrent(aDC2Volt(analogRead(aDCCurrent)))); //push value into average array //print input voltage value and current values #ifdef FASTMEAS #ifdef FASTAMP Serial.println(currMeas.get((currMeas.getCount() - 1))*1000); //serial print out of fast current measurements #else Serial.println(voltMeas.get((voltMeas.getCount() - 1))); //serial print out of fast voltage measurements #endif #endif mStart = millis(); //reset timer } //print out average, max / min, and amp hour measurements if(voltMeas.getCount() == (measAvgInt/measInterval)) { #ifdef AVGMEAS Serial.print("Average voltage: "); Serial.print(voltMeas.mean()); Serial.println(" V"); //get and print average voltage value float mA = currMeas.mean()*1000; //get average current value in mA Serial.print("Average current: "); Serial.print(mA); Serial.println(" mA"); //print current value Serial.print("Max voltage: "); Serial.print(voltMeas.maximum()); Serial.println(" V"); //print max and min voltage Serial.print("Min voltage: "); Serial.print(voltMeas.minimum()); Serial.println(" V"); Serial.print("Max current: "); Serial.print(currMeas.maximum()*1000); Serial.println(" mA"); //print max and min current Serial.print("Min current: "); Serial.print(currMeas.minimum()*1000); Serial.println(" mA"); float aH = ampHoursCal(measAvgInt,mA); //calculate how much amp hours of current was consumed since start if(aH < 1000) { Serial.print("Amp hours of power source: "); Serial.print(aH); Serial.println(" uAh"); } //print current in uA else { Serial.print("Amp hours of power source: "); Serial.print(aH/1000); Serial.println(" mAh"); } //print current in mA #endif voltMeas.clear(); //clear voltage measurement array currMeas.clear(); //clear current measurement array } if(repeat > 0) repeat--; //increment repeat if not infinite loop } } //timer function that runs in mill second steps. //Inputs are timer interval and timer start time bool timer(unsigned long tInterval, unsigned long tStart) { unsigned long now = millis(); //get timer value if ((now - tStart) > tInterval ) return true; //check if interval is up return false; //interval is not up } //converts raw ADC reading to voltage value based on 3.3V reference //input is 12 bit ADC value float aDC2Volt(int aDC) { return (((float)aDC/4095)*3.3); } //function converts voltage value to input voltage value based off resistor voltage divider constant //input is measured voltage float inputVolt(float aVolt) { return (rMult*aVolt); } //converts voltage measurement at load resistor to current measurement based on load resistor value //Input is measured voltage float inputCurrent(float rVolt) { return (rVolt/lRes); } //This functions calculates amp hours //amp hour = amp hour value + (amps * (mil sec / 360k) //input: measInt is measurement interval in milli sec and aVal is the measured current value in mA float ampHoursCal(int measInt, float aVal) { aHours = aHours + (aVal * ((double)measInt/m2Hours)*1000); //this converts currect measurement to mA return aHours; }



Wednesday, October 11, 2017

How to Build a Simple DC Electronic Load with Arduino Part 1

In this video we look at how to make a simple DC electronic load with Arduino and some simple components.





//****************Arduino code from video************
/*
 * This code was used for a tutorial on how to build a simple eload with Arduino
 * The Tutorial can be found on the ForceTronics YouTube Channel
 * This code is public domain and free for anybody to use at their own risk
 */
void setup() {
  pinMode(A0, OUTPUT); //A0 DAC pin to output
  analogWriteResolution(10); //default DAC resolution is 8 bit, swith it to 10 bit (max)
}

void loop() {
  //create pulsed current profile
  analogWrite(A0, 16); //Set DAC to approximately 10mV --> current 10mV / 5ohm = 2 mA
  delay(500);
  analogWrite(A0,310); //Set DAC to 1V --> current 1V / 5ohm = 200 mA
  delay(50);

}

Monday, September 11, 2017

Two Methods for Soldering Surface Mount Components by Hand

When you are prototyping, repairing, or hacking PCB boards you will most definitely find yourself in situations where you need to solder surface mount components / devices (SMD) by hand. In this video we look at two easy methods to solder SMD by hand with a basic solder station.


Wednesday, September 6, 2017

Easy Way to Design a PCB for the Ublox Neo-7m GNSS / GPS Module Part 2

In this tutorial we look at how easy it is to integrate the popular Neo-7m GNSS / GPS module into your design without having to be an RF / microwave expert. In part 2 we build up our board and take it for a test drive.




Link to Eagle files on GitHub: https://github.com/ForceTronics/Neo-7m_Eagle_Design/tree/master

Friday, August 25, 2017

Easy Way to Design a PCB for the Ublox Neo-7m GNSS / GPS Module

In this tutorial we look at how easy it is to integrate the popular Neo-7m GNSS / GPS module into your design without having to be an RF / microwave expert.


Link to Eagle files on GitHub: https://github.com/ForceTronics/Neo-7m_Eagle_Design/tree/master

Thursday, August 10, 2017

Getting Started with Arduino and the ThingSpeak Cloud

In this video we look at how to use Arduino with the ThingSpeak IoT, cloud, and analytics platform. In the video we look at two use cases of ThingSpeak. For the first use case we log wireless sensor data to the cloud and perform post processing on the data using MATLAB. In the second use case we monitor a room with a wireless motion detector setup and have ThingSpeak send out a Tweet if any movement is detected in the room.



//*****************Arduino code from video**********************************
/*
This sketch was created for a video tutorial on the ForceTronics YouTube that shows how to use Arduino with the ThingSpeak cloud
This code is public domain and free for anybody to use or modify at their own risk

Note this code was leveraged from:
 Arduino --> ThingSpeak Channel via MKR1000 Wi-Fi
 Created: May 7, 2016 by Hans Scharler (http://www.nothans.com)
*/
   
#include <SPI.h>
#include <WiFi101.h> //This sketch should work with any Arduino or shield that can use the WiFi101 library

char ssid[] = "YourNetwork"; //  your network SSID (name)
char pass[] = "YourPassword"; // your network password

int status = WL_IDLE_STATUS;

// Initialize the Wifi clients
WiFiClient tClient; //this one is used to post temperature data
WiFiClient mClient; //this one is used to post motion detection data

// ThingSpeak Settings
char server[] = "api.thingspeak.com";
String writeAPIKey = "YourWriteKey";

//Timing variables for tracking temperature posting
unsigned long tempLastConnectionTime = 0; // track the last connection time
const unsigned long tempPostingInterval = 295000L; // post temp ADC value just under every 5 min

//Timing and logic variables for tracking temperature posting
unsigned long mLastConnectionTime = 0; // track the last connection time
const unsigned long mPostingInterval = 30000L; //checks to see if motion was detected every 30 sec
bool mReset = true; //tracks if motion detection has been reset

void setup() {
  pinMode(2,INPUT); //digital pin used to read output of motion detector
  pinMode(6,OUTPUT); //LED pin used to know when data is sent to cloud
  
  // attempt to connect to Wifi network
  while ( status != WL_CONNECTED) {
    // Connect to WPA/WPA2 Wi-Fi network
    status = WiFi.begin(ssid, pass);
    // wait 10 seconds for connection
    delay(10000);
  }
}

void loop() {
  //timer to know when it is time to post temp data to cloud
  if (millis() - tempLastConnectionTime > tempPostingInterval) {
    digitalWrite(6,HIGH); //Use the LED to see if Arduino gets heldup posting data to the cloud
    tempHttpRequest(); //function that formats data strings and posts data to ThingSpeak cloud
    digitalWrite(6,LOW);
  }

  if (millis() - mLastConnectionTime > mPostingInterval) {
    digitalWrite(6,HIGH); //Use the LED to see if Arduino gets heldup posting data to the cloud
    if(digitalRead(2) && mReset) { //if motion was detected post it
      mReset = false; //motion detected so reset variable
      mHttpRequest(); //if true motion was detected so post to cloud
    }
    else mReset = true; //reset logic tracker
    
    digitalWrite(6,LOW);
  }

}

//Posts temp data to thingspeak cloud
void tempHttpRequest() {
  // read analog pin 0 with temp sensor connected
  int sensorValue = analogRead(0);

  // create data string to send to ThingSpeak
 String data = String("field1=" + String(sensorValue, DEC)); 

  // POST data to ThingSpeak
  if (tClient.connect(server, 80)) {
    tClient.println("POST /update HTTP/1.1");
    tClient.println("Host: api.thingspeak.com");
    tClient.println("Connection: close");
    tClient.println("User-Agent: ArduinoWiFi/1.1");
    tClient.println("X-THINGSPEAKAPIKEY: "+writeAPIKey);
    tClient.println("Content-Type: application/x-www-form-urlencoded");
    tClient.print("Content-Length: ");
    tClient.print(data.length());
    tClient.print("\n\n");
    tClient.print(data);
     // close any connection before sending a new request
    tClient.stop();
    // note the last connection time
    tempLastConnectionTime = millis();
  }
}

//posts motion detection data to thingspeak cloud
void mHttpRequest() {

  // create data string to send to ThingSpeak, we always send a one here to indicate motion detected
 String data = String("field2=" + String(1,DEC)); 

  // POST data to ThingSpeak
  if (mClient.connect(server, 80)) {
    mClient.println("POST /update HTTP/1.1");
    mClient.println("Host: api.thingspeak.com");
    mClient.println("Connection: close");
    mClient.println("User-Agent: ArduinoWiFi/1.1");
    mClient.println("X-THINGSPEAKAPIKEY: "+writeAPIKey);
    mClient.println("Content-Type: application/x-www-form-urlencoded");
    mClient.print("Content-Length: ");
    mClient.print(data.length());
    mClient.print("\n\n");
    mClient.print(data);
     // close any connection before sending a new request
    mClient.stop();
    // note the last connection time
    mLastConnectionTime = millis();
  }
}

%*************************MATLAB code from video***************************
% Channel ID to read raw ADC temp data from
readChannelID = chanID;
% Temperature Field ID
TemperatureFieldID = 1;

% Channel Read API Key 
readAPIKey = 'YourReadKey';

% Channel ID to write temp data to:
writeChannelID = [chanID];
% API key for write channel:
writeAPIKey = 'YourWriteKey';

%Read raw ADC temp data
aDC = thingSpeakRead(readChannelID, 'Fields', TemperatureFieldID, 'ReadKey', readAPIKey);

%Convert raw 10 bit ADC data to voltage
volt = aDC*(3.3/1023);

%Using analog temp sensor TMP36
%calculate temp in C, .75 volts is 25 C. 10mV per degree
 if volt < .75 
     temp = 25 - ((.75-volt)/.01); %if below 25 C
 elseif volt == .75 
         temp = 25;
 else 
     temp = 25 + ((volt -.75)/.01);  %if above 25
 end

% Convert to Fahrenheit
tempF = (9/5*temp) + 32;

%This writes temp value to below console for debugging
display(tempF);

%write temp F value to channel
thingSpeakWrite(writeChannelID, 'Fields',1,'Values',tempF, 'Writekey', writeAPIKey);

Saturday, June 10, 2017

Using Compiler Directives with Arduino

In this video we look at what are compiler directives and how they can come in handy.



//***********************Arduino code from the video***********
/*
 * This code was made for a video tutorial on ForceTronics YouTube Channel called "Using Compiler Directives with Arduino"
 * This code free to be used or modified by anybody at your own risk
 * 
 */


//#define SERIAL_PRINT 1
#define ADC_PIN (uint8_t)A0

 #ifdef SERIAL_PRINT
  #define _SERIAL_BEGIN(x) Serial.begin(x);
  #define _SERIAL_PRINT(x) Serial.print(x);
  #define _SERIAL_PRINTLN(x) Serial.println(x);
 #else
  #define _SERIAL_BEGIN(x)
  #define _SERIAL_PRINT(x)
  #define _SERIAL_PRINTLN(x)
 #endif


void setup() {
  
  _SERIAL_BEGIN(57600); //start serial comm if enabled

  //This will only print if SERIAL_PRINT is 1
  _SERIAL_PRINTLN("We are going to take an ADC reading every 2 sec...");

}

void loop() {
  _SERIAL_PRINT("The latest ADC measurement is ");
  _SERIAL_PRINTLN(analogRead(ADC_PIN));
  delay(2000); 

}

Tuesday, May 30, 2017

Home Automation with Arduino and the Amazon Echo Part 4

In the final conclusion of this four part series on using the Amazon Echo and Arduino for home automation we look at the Arduino hardware setup for monitoring the current consumption of a washer machine and reports its state to the cloud.




You can access code from GitHub: https://github.com/ForceTronics/Arduino_Echo_Home_Automation


Friday, May 26, 2017

Home Automation with the Arduino and the Amazon Echo Part 3

In part 3 instead of controlling a household device with the Echo, Arduino, and the cloud like we did in parts 1 and 2, we are monitoring an appliance (washer) so the data is flowing in the opposite direction.



You can access the code on github:  https://github.com/ForceTronics/Arduino_Echo_Home_Automation



Sunday, April 30, 2017

Building a Custom Strain Gauge with Electric Paint

In this video we look at how we can use Bare Conductive's Electric Paint to create a custom strain gauge.




/*
 * This code was written for a video on the ForceTronics YouTube channel. This code is public domain and can be used and modified by anybody at your own risk
 */

#include <Average.h> //Call average library

void setup() {
  Serial.begin(57600);
  analogReadResolution(12); //Set Arduino Zero ADC to 12 bits
  for(int i=0;i<4;i++) analogRead(A0); //burn a couple readings since we changed ADC setting
  Average<int> ave(10);
}

void loop() {
  delay(100);
  Average<int> ave(10); //Create average object
  for (int i=0; i<10;i++) ave.push(analogRead(A0) - 2700); //get 10 readings and subtract most of the value off to look at small changes
  Serial.println(ave.mean()); //average the 10 readings together
}

Thursday, April 6, 2017

Home Automation with the Arduino and the Amazon Echo Part 2

In this video series we look at how to use Arduino (ESP8266) and the Amazon Echo to do voice controlled home automation.






Link to project material on GitHub: https://github.com/ForceTronics/Arduino_Echo_Home_Automation

//************************************ESP8266 Arduino code*********************
/*
 This sketch was created for a video series called Home Automation with the Arduino and the Amazon Echo Part 2 
 That was presented on the ForceTronics YouTube Channel. This code is public domain for anybody to use or modify at your own risk
 Note that this code was leveraged from a Sparkfun example on using their cloud service Phant
 */

// Include the ESP8266 WiFi library
#include <ESP8266WiFi.h>
// Include the SparkFun Phant library.
#include <Phant.h>

//Set your network name and password
const char WiFiSSID[] = "NetworkName"; //your wifi network name goes here
const char WiFiPSK[] = "NetworkPassword"; //your wifi password goes here

//define constants for pin control and node number
const int light = 4; //NodeMCU GPIO 4 pin is connected to the WiFi AC Switch control
const char parseKey[] = "stamp"; //This is used to parse through data from Phant to find light setting

//declare phant address and security keys
const char PhantHost[] = "data.sparkfun.com";
const char gPublicKey[] = "YourPublicKey"; //your phant public key goes here
const char gPrivateKey[] = "YourPrivateKey"; //your phant private key goes here

//specify the rate that you post data to cloud
const unsigned long postRate = 1000;
unsigned long lastPost = 0;

void setup() 
{
  initHardware(); //setup arduino hardware
  connectWiFi(); //Connect your WiFi network
  digitalWrite(LED_BUILTIN, HIGH); //turn on LED
}

void loop() 
{ //loop until it is time to post data to phant cloud, variable "postRate" defines the interval in milli seconds
  if (lastPost + postRate <= millis())
  {
    if (getFromPhant()) lastPost = millis(); //get data from Phant
    else lastPost = millis(); //Even if we fail delay whole cycle before we try again
  }
}

//function used to connect to WiFi network
void connectWiFi()
{
  byte ledStatus = LOW;
  // Set WiFi mode to station (as opposed to AP or AP_STA)
  WiFi.mode(WIFI_STA);
  // WiFI.begin([ssid], [passkey]) initiates a WiFI connection
  // to the stated [ssid], using the [passkey] as a WPA, WPA2,
  // or WEP passphrase.
  WiFi.begin(WiFiSSID, WiFiPSK);
  
  // Use the WiFi.status() function to check if the ESP8266
  // is connected to a WiFi network.
  while (WiFi.status() != WL_CONNECTED)
  {
    // Blink the LED
    digitalWrite(LED_BUILTIN, ledStatus); // Write LED high/low
    ledStatus = (ledStatus == HIGH) ? LOW : HIGH;
    
    // Delays allow the ESP8266 to perform critical tasks
    // defined outside of the sketch. These tasks include
    // setting up, and maintaining, a WiFi connection.
    delay(100);
  }
}

//function that sets up some initial hardware states
void initHardware()
{
  pinMode(light, OUTPUT); //turn light off at startup
  digitalWrite(light, LOW);
}

//function that handles getting data from phant cloud
int getFromPhant()

 //Set phant data
 Phant phant(PhantHost, gPublicKey, gPrivateKey);
  
  WiFiClient client; //Create client object to communicate with the phant server

  if (!client.connect(PhantHost, 80)) { //Attempt to connect to phant server using port 80
    // If we fail to connect, return 0.
    return 0;
  }

  //Get data from phant cloud
    client.print(phant.get()); 
    client.println();
   int cTrack = 0; //variable that tracks count to spell stamp
   bool match = false; //tracks when we have a match with "stamp" and we can then get control data
   int pCount = 0; //variable used to track when we have control data
   while(1) { //loop until we get data and server closes connection
    if (client.available()) { //if data is available from phant server
      char c = client.read(); //read a bite of data from server
      if(!match) { //if true than we have not found the word "stamp" so keep looking
        if(c == parseKey[cTrack]) //check if we have a character match with word "stamp"
        {
          if(cTrack == (sizeof(parseKey)-2)) match = true; //if true it means we found a match for "stamp" in data from phant cloud
          cTrack++; //iterate this count if a character match was found
        }
        else { //if true means no character match so reset count
          cTrack = 0;
        }
      }
      else { //if true it means we found a match to "stamp" and we are ready to get control data
        
        if(pCount == 1) { //if true we are at the point in the data to read control data for node oen
          int dControl = c - '0'; //convert char data to an int by subtract an ASCII zero
          if(dControl == 1 | dControl == 0) digitalWrite(light, dControl); //make sure data is a one or zer and set LED pin with it
        }
        pCount++; //iterate the parse counter
      }
    }

    // if the server's disconnected, stop the client:
    if (!client.connected()) {
      client.stop(); //stop client, if you don't have this you will create too many clients and server won't let you connect anymore
      break; //This is how we get out of the loop
    }
   }
  
  return 1; // Return success
}

  

Sunday, April 2, 2017

Home Automation with the Arduino and the Amazon Echo Part 1

In this video series we look at how to use Arduino (ESP8266) and the Amazon Echo to do voice controlled home automation.



//*******************json file for Alexa Skill*****************
{
  "intents": [
    {
      "intent": "TurnLightOn"
    },
    {
      "intent": "TurnLightOff"
    }
  ]
}

//********************java script code for Lambda Function*************************
var https = require('https') //include https

exports.handler = (event, context) => {

  try {

    if (event.session.new) {
      // New Session
      console.log("NEW SESSION") //log this for debugging
    }

    switch (event.request.type) {

      case "LaunchRequest":
        // Launch Request
        console.log(`LAUNCH REQUEST`)
        context.succeed(
          generateResponse(
            buildSpeechletResponse("Welcome to the ForceTronics Home Automation Skill, say turn light on or turn light off", true), //response for Alexa if you just call the skill without intent
            {}
          )
        )
        break;

      case "IntentRequest":
        // Intent Request
        console.log(`INTENT REQUEST`)

        switch(event.request.intent.name) { //switch statement to select the right intent
          case "TurnLightOn":
          var endpoint = "https://data.sparkfun.com/input/YourPublicKey?private_key=YourPrivateKey&lightstate=1" //https string to log data to phant phant
          https.get(endpoint, function (result) { //use https get request to send data to phant
          console.log('Success, with: ' + result.statusCode);
          context.succeed(
           generateResponse( //if you succeeded allow Alexa to tell you state of light
                buildSpeechletResponse("The light is turned on", true),
                {}
            )
          )
          }).on('error', function (err) {
            console.log('Error, with: ' + err.message);
            context.done("Failed");
          });
            break;

          case "TurnLightOff": //the turn light off intent
            var endpoint2 = "https://data.sparkfun.com/input/YourPublicKey?private_key=YourPrivateKey&lightstate=0" // phant string to set light state to off
            https.get(endpoint2, function (result) {
            console.log('Success, with: ' + result.statusCode);
            context.succeed(
                generateResponse( //Alexa response if successful
                 buildSpeechletResponse("The light is turned off", true),
                    {}
                )
            )
            }).on('error', function (err) {
            console.log('Error, with: ' + err.message);
            context.done("Failed");
            });
            break;

          default:
            throw "Invalid intent"
        }

        break;

      case "SessionEndedRequest":
        // Session Ended Request
        console.log(`SESSION ENDED REQUEST`)
        break;

      default:
        context.fail(`INVALID REQUEST TYPE: ${event.request.type}`)

    }

  } catch(error) { context.fail(`Exception: ${error}`) }

}

// builds an Alexa response
buildSpeechletResponse = (outputText, shouldEndSession) => {

  return {
    outputSpeech: {
      type: "PlainText",
      text: outputText
    },
    shouldEndSession: shouldEndSession
  }

}

//plays Alexa reponse
generateResponse = (speechletResponse, sessionAttributes) => {

  return {
    version: "1.0",
    sessionAttributes: sessionAttributes,
    response: speechletResponse
  }

}

Tuesday, March 28, 2017

How to Remove Solder Bridges

In this video we look at how to remove solder bridges from small surface mount components. When dealing with really small pins the task of removing solder bridges can seem intimidating, but as you will see in this video it is not tough at all if you have the right tools and know how for the job.



Supplies used in solder bridge tutorial

Wednesday, March 22, 2017

Reduce Noise in Your Sensor Measurements with an Active Low Pass Filter Part 3

In this three part series we look at how to design a signal conditioning circuit to increase the accuracy and resolution of your ADC sensor measurements. The signal conditioning circuit consists of a double pole active Sallen Key Low Pass Filter and a non-inverting op amp. The filter portion is meant to attenuate high frequency noise from your sensor signal to increase measurement accuracy. The amplifier portion scales the signal up to the full range of the ADC to ensure you are getting max resolution. In part 3 we test our finished LPF + Amp circuit. 




If you are interested in purchasing the circuit from the video go to forcetronics.com

You can access the Eagle files on Github at: https://github.com/ForceTronics/Salle...


Sunday, March 5, 2017

Reduce Noise in Your Sensor Measurements with an Active Low Pass Filter Part 2

In this three part series we look at how to design a signal conditioning circuit to increase the accuracy and resolution of your ADC measurements. The signal conditioning circuit consists of a double pole active Sallen Key Low Pass Filter and a non-inverting op amp. The filter portion is meant to attenuate high frequency noise from your sensor signal to increase measurement accuracy. The amplifier portion scales the signal up to the full range of the ADC to ensure you are getting max resolution. In part 2 we do the PCB layout of our circuit using Eagle CAD software.





You can access the Eagle files on Github at: https://github.com/ForceTronics/Sallen-Key-Low-Pass-Filter-Design/tree/master


Monday, February 27, 2017

Reduce Noise in Your Sensor Measurements with an Active Low Pass Filter Part 1

In this three part series we look at how to design a signal conditioning circuit to increase the accuracy and resolution of your ADC measurements. The signal conditioning circuit consists of a double pole active Sallen Key Low Pass Filter and a non-inverting op amp. The filter portion is meant to attenuate high frequency noise from your sensor signal to increase measurement accuracy. The amplifier portion scales the signal up to the full range of the ADC to ensure you are getting max resolution.




You can find the online filter calculator used in part one at this link: http://sim.okawa-denshi.jp/en/OPseikiLowkeisan.htmk

You can access the LTspice file on Github at: https://github.com/ForceTronics/Sallen-Key-Low-Pass-Filter-Design/tree/master

Sallen-Key Low Pass Filter Circuit with Amplifier Stage in LTspice

Wednesday, February 1, 2017

Accessing Hidden Pins on the Arduino Zero

In this video we look at how you can access six additional digital pins from your Arduino Zero board. We also take a look at some flexible wired communication options you can take advantage of on the Arduino Zero.






Link to Adafruit tutorial referenced in the video: https://learn.adafruit.com/using-atsamd21-sercom-to-add-more-spi-i2c-serial-ports/creating-a-new-serial

Path on Windows to get to variants.cpp: C:\Users\yourname\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.6.6

Zero pin out chart from video:


//**********************Arduino Code from the video*********************
//This code is free to use and modify at your own risk

bool tog = false; //used to toggle LEDs on and off

void setup() {
  pinMode(38,OUTPUT); //This is the pin labeled "ATN"
  pinMode(22,OUTPUT); //This is MISO pin on ICSP header
  pinMode(20,OUTPUT); //This is SDA pin
  SerialUSB.begin(57600); //this is the native USB port
  Serial.begin(57600); //this is the programming port
  Serial1.begin(57600); //this is for pins D0 and D1
}

void loop() {

  if(tog) { //set each of the pins to high to turn LEDs on
    digitalWrite(38,HIGH);
    digitalWrite(22,HIGH);
    digitalWrite(20,HIGH);
    tog = false;
  }
  else { //set each pin to low to turn them off
    digitalWrite(38,LOW);
    digitalWrite(22,LOW);
    digitalWrite(20,LOW);
    tog = true;
  }

  delay(1500); //delsy for 1.5 seconds
}