Archive for the Category ◊ Electronics ◊
I’m planning to create a digital “pin-art” board – something similar to the photo below.
Source: http://cdn.visualnews.com/wp-content/uploads/2011/05/Lulu-Guinness-11.jpg
Continuing from Standalone Arduino and Thermometer and Humidity Control, created a standalone thermometer and humidity control. Added the following features:
Now that the circuit for my Temperature and Humidity Control is working – its time to create a standalone micro-controller circuit so that I can free up my Induino.
http://arduino.cc/en/Tutorial/ArduinoToBreadboard
http://arduino.cc/en/Hacking/PinMapping168
http://www.instructables.com/id/The-RRRRRRRRRRBA-or-What-They-Dont-Teach-You-in-/step5/Some-Caveats/
All-in ~250 bucks. Had a 9V 1A power supply at home – so that was free. Needed a 9V for the relays that I had – otherwise you can use a 5V USB adapter that comes with most mobiles and gadgets. I have 8-10 lying at home 🙂
Wire up the components as per the diagram below:
You can disconnect the cables from your Arduino to the standalone board
Since our clone doesn’t have a USB-TTL interface, we have to use our arduino to program it. (this is one of the limitations :-))
The first thing that came to my mind when I started microcontroller programming was to set an automatic room heating cum humidifier system.
First off – bought a DHT11 sensor module. Then went about setting up the circuit. Added the LCD to boot – to show the temperature and humidity.
Set up the circuit as follows:
Code as follows:
#include
#include
#define DHT11PIN 13
#define RELAY1 2 // Connect humidifier to Relay1
#define RELAY2 3 // Connect heater to Relay2
#define TEMP_SET 20.0
#define HUM_SET 35.0
dht11 DHT11;
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);
void setup() {
lcd.begin(16, 2);
pinMode(DHT11PIN, INPUT);
pinMode(RELAY1, OUTPUT);
pinMode(RELAY2, OUTPUT);
}
void loop() {
// put your main code here, to run repeatedly:
int chk = DHT11.read(DHT11PIN);
// Serial.print("Read sensor: ");
switch (chk)
{
case DHTLIB_OK:
// Serial.println("OK");
break;
case DHTLIB_ERROR_CHECKSUM:
// Serial.println("Checksum error");
break;
case DHTLIB_ERROR_TIMEOUT:
// Serial.println("Time out error");
break;
default:
lcd.println("Unknown error");
break;
}
lcd.setCursor(0, 0);
lcd.print("Humidity: ");
lcd.print((float)DHT11.humidity, 2);
lcd.setCursor(0, 1);
lcd.print("Temp: ");
lcd.print((float)DHT11.temperature, 2);
if(DHT11.humidity < 50){
digitalWrite(RELAY1, HIGH);
lcd.print("H1");
}
else {
digitalWrite(RELAY1,LOW);
// lcd.print("H0");
}
if(DHT11.temperature < 25){
digitalWrite(RELAY2, HIGH);
// lcd.print("T1");
}
else {
digitalWrite(RELAY2,LOW);
lcd.print("T0");
}
delay(900000);
}
Worked like a charm – next steps:
Continuing my saga with electronics – went for an electronics workshop by Kits’n’Spares – the workshop was nothing to talk about – however did get me a Mango Pi – a development board for the PIC processors.
Well surprise – surprise – doesn’t support Mac OS, at least I couldn’t get it to work. Finally gave up, started Windows XP in parallels, downloaded the software and started programming. Its not as easy as the arduino, but fun nevertheless. Took me a whole day to program the LCD. The code samples provided with the kit didn’t work and had to troll through the net to understand how to make it work. Finally got it working, here’s the code:
/*
* File: LCT Trial.c
*
* Created on October 6, 2013, 7:56 PM
*/
#include
#include
#include
/*
*
*/
// PIC16F877A Configuration Bit Settings
#include
// #pragma config statements should precede project file includes.
// Use project enums instead of #define for ON and OFF.
// CONFIG
#pragma config FOSC = XT // Oscillator Selection bits (XT oscillator)
#pragma config WDTE = OFF // Watchdog Timer Enable bit (WDT disabled)
#pragma config PWRTE = OFF // Power-up Timer Enable bit (PWRT disabled)
#pragma config BOREN = OFF // Brown-out Reset Enable bit (BOR disabled)
#pragma config LVP = ON // Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit (RB3/PGM pin has PGM function; low-voltage programming enabled)
#pragma config CPD = OFF // Data EEPROM Memory Code Protection bit (Data EEPROM code protection off)
#pragma config WRT = OFF // Flash Program Memory Write Enable bits (Write protection off; all program memory may be written to by EECON control)
#pragma config CP = OFF // Flash Program Memory Code Protection bit (Code protection off)
/*
*
*/
char name1[32]={"Lots of Love -- Dushyant "};
int counter=0;
void delay(int x)
{
int d,l;
for(l=0;l<x;l++)
{
for(d=0;d<1000;d++);
}
}
void instwrt(int x)
{
PORTC=0b00000100;
PORTD=x;
PORTC=0b00000000;
delay(1);
PORTC=0b00000100;
}
void datawrt(int x)
{
PORTC=0b00000101;
PORTD=x;
PORTC=0b00000001;
delay(1);
PORTC=0b00000101;
counter++;
if (counter==16){
instwrt(0xC0);
}
if (counter==32){
instwrt(0x80);
}
}
void lcdin()
{
delay(5);
instwrt(0b00001111);
instwrt(0b00111101);
instwrt(0b00000010);
instwrt(0b00000001);
}
void main(void) {
int a;
TRISB = 0x00;
PORTB = 0b00000010;
TRISD=0x00;
TRISC=0X00;
//PORTC=0b00000010;
// PORTD=
lcdin();
PORTB=0b010;
for(a=0;a<32;a++)
{
datawrt(name1[a]);
delay(5);
// PORTB=name1[a];
}
while(1)
{
instwrt(0x18);
delay(50);
}
}