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@sankarcheppali
sankarcheppali / main.js
Created March 29, 2017 17:56
Intel Edison Temperature Logger With RBG-LCD
// Load Grove module
var groveSensor = require('jsupm_grove');
var FormData = require('form-data');
var fs = require('fs');
// we want mraa to be at least version 0.6.1
var mraa = require('mraa');
var version = mraa.getVersion();
var tSampFileName='t_samp.csv';
04-24 22:12:03.830 18041-18139/com.xxx.xxx.smarthook E/AndroidRuntime: FATAL EXCEPTION: MQTT Con: 02:00:00:00:00:00
Process: com.xxx.xx.smarthook, PID: 18041
java.lang.NullPointerException: cancel() called with a null PendingIntent
at android.app.AlarmManager.cancel(AlarmManager.java:890)
at org.eclipse.paho.android.service.AlarmPingSender.stop(AlarmPingSender.java:86)
at org.eclipse.paho.client.mqttv3.internal.ClientComms.shutdownConnection(ClientComms.java:327)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:608)
@sankarcheppali
sankarcheppali / delay.c
Created April 25, 2017 07:05
dc motor speed control
#include<reg51.h>
void delay_us(unsigned int us_count)
{
while((us_count*4)!=0)
{
us_count--;
}
}
@sankarcheppali
sankarcheppali / pi_opencv
Created June 14, 2017 09:31
install dependencies for face detection on raspberry pi
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install build-essential
sudo apt-get install cmake git libgtk2.0-dev pkg-config libavcodec-dev libavformat-dev libswscale-dev
sudo apt-get install python-dev python-numpy libjpeg-dev libpng-dev libtiff-dev libjasper-dev libdc1394-22-dev
sudo apt-get install python-opencv
sudo apt-get install opencv
sudo apt-get install python-matplotlib
import io
import picamera
import cv2
import numpy
#Create a memory stream so photos doesn't need to be saved in a file
stream = io.BytesIO()
#Get the picture (low resolution, so it should be quite fast)
#Here you can also specify other parameters (e.g.:rotate the image)
#Load a cascade file for detecting faces
face_cascade = cv2.CascadeClassifier('/home/pi/Desktop/opencv/haarcascade_frontalface_default.xml')
eye_cascade = cv2.CascadeClassifier('/home/pi/Desktop/opencv/haarcascade_eye.xml')
#Convert to grayscale
gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
#Look for faces in the image using the loaded cascade file
faces = face_cascade.detectMultiScale(gray, 1.3, 5)
@sankarcheppali
sankarcheppali / ShiftOut
Created June 16, 2017 06:22
The following function can push 16 bits of data to the shift registers (assuming two shifts registers cascaded)
serOut=2 --SER pin
clk=1 --shift register clock (SRCLK)
latch=3 -- Storage register clock (RCLK)
loadStatus=0 --use only 16 bits
gpio.mode(clk,gpio.OUTPUT)
gpio.mode(serOut,gpio.OUTPUT)
gpio.mode(latch,gpio.OUTPUT)
local function sendClk()
local function consume_data( payload )
--we will parse the payload and excute it,publish the return value
print(payload)
msg=cjson.decode(payload)
loadNumber=msg.ln
targetStatus=msg.ts
if(targetStatus==0) then loadStatus=bit.clear(loadStatus,loadNumber)
else loadStatus = bit.set(loadStatus,loadNumber) end
serialOut(loadStatus)
print ("Status of the loads : ")
package example.siva.com.hellokotlin
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_main.*
import org.jetbrains.anko.toast
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {