Wireless temperature and humidity sensor with RF modules - Revision history

Admin at 06:36, 5 April 2012

2012-04-05T06:36:58Z

← Older revision		Revision as of 06:36, 5 April 2012
Line 125:		Line 125:
	digitalWrite(13, true); // Flash a light to show received good message		digitalWrite(13, true); // Flash a light to show received good message
	Serial.print("Got: ");		Serial.print("Got: ");
			// Message with a good checksum received, dump it.
	for (i = 0; i < buflen; i++)		for (i = 0; i < buflen; i++)
	{		{

Admin at 06:36, 5 April 2012

2012-04-05T06:36:12Z

← Older revision		Revision as of 06:36, 5 April 2012
Line 124:		Line 124:
	{ int i;		{ int i;
	digitalWrite(13, true); // Flash a light to show received good message		digitalWrite(13, true); // Flash a light to show received good message
	~~// Message with a good checksum received, dump it.~~
	Serial.print("Got: ");		Serial.print("Got: ");
	for (i = 0; i < buflen; i++)		for (i = 0; i < buflen; i++)
	{		{
	if (buf[i]==255){ lcd.cursorTo(1,0);		if (buf[i]==255){ lcd.cursorTo(1,0);
	}		}
	lcd.print(buf[i]);		lcd.print(buf[i]);

Admin at 06:35, 5 April 2012

2012-04-05T06:35:06Z

← Older revision		Revision as of 06:35, 5 April 2012
Line 122:		Line 122:
	uint8_t buflen = VW_MAX_MESSAGE_LEN;		uint8_t buflen = VW_MAX_MESSAGE_LEN;
	if (vw_get_message(buf, &buflen)) // Non-blocking		if (vw_get_message(buf, &buflen)) // Non-blocking
	{		{ int i;
	int i;
	digitalWrite(13, true); // Flash a light to show received good message		digitalWrite(13, true); // Flash a light to show received good message
	// Message with a good checksum received, dump it.		// Message with a good checksum received, dump it.
	Serial.print("Got: ");		Serial.print("Got: ");

	for (i = 0; i < buflen; i++)		for (i = 0; i < buflen; i++)
	{		{

Admin at 06:34, 5 April 2012

2012-04-05T06:34:34Z

← Older revision		Revision as of 06:34, 5 April 2012
Line 44:		Line 44:
	#define DHTTYPE DHT11 // DHT 11		#define DHTTYPE DHT11 // DHT 11
	DHT dht(DHTPIN, DHTTYPE);		DHT dht(DHTPIN, DHTTYPE);

	#include <VirtualWire.h>		#include <VirtualWire.h>
	#undef int		#undef int
Line 61:		Line 60:
	}		}
	void loop() {		void loop() {

	int humidity = dht.readHumidity();		int humidity = dht.readHumidity();
	int temp = dht.readTemperature();		int temp = dht.readTemperature();

	// check if returns are valid, if they are NaN (not a number) then something went wrong!		// check if returns are valid, if they are NaN (not a number) then something went wrong!
	if (isnan(humidity) \|\| isnan(temp)) {		if (isnan(humidity) \|\| isnan(temp)) {
Line 113:		Line 110:
	Serial.begin(9600); // Debugging only		Serial.begin(9600); // Debugging only
	Serial.println("setup");		Serial.println("setup");

	// Initialise the IO and ISR		// Initialise the IO and ISR
	vw_set_ptt_inverted(true); // Required for DR3100		vw_set_ptt_inverted(true); // Required for DR3100
Line 123:		Line 119:
	void loop()		void loop()
	{		{

	uint8_t buf[VW_MAX_MESSAGE_LEN];		uint8_t buf[VW_MAX_MESSAGE_LEN];
	uint8_t buflen = VW_MAX_MESSAGE_LEN;		uint8_t buflen = VW_MAX_MESSAGE_LEN;

	if (vw_get_message(buf, &buflen)) // Non-blocking		if (vw_get_message(buf, &buflen)) // Non-blocking
	{		{
	int i;		int i;

	digitalWrite(13, true); // Flash a light to show received good message		digitalWrite(13, true); // Flash a light to show received good message
	// Message with a good checksum received, dump it.		// Message with a good checksum received, dump it.
Line 139:		Line 132:
	if (buf[i]==255){ lcd.cursorTo(1,0);		if (buf[i]==255){ lcd.cursorTo(1,0);
	}		}

	lcd.print(buf[i]);		lcd.print(buf[i]);
	}		}
	}		}
	}		}

Admin at 06:33, 5 April 2012

2012-04-05T06:33:47Z

← Older revision		Revision as of 06:33, 5 April 2012
Line 38:		Line 38:

	There are two methods for expanding the range and efficiency of these two devices. Each transmitter device has a supply voltage range of 2 – 12 volts. The higher the voltage, the stronger the signal strength. Also, the use of an optional antenna will increase the effectiveness of your wireless communication. A simple wire will do the trick, with different antenna shapes and configurations based on the shape make of your project for best results.		There are two methods for expanding the range and efficiency of these two devices. Each transmitter device has a supply voltage range of 2 – 12 volts. The higher the voltage, the stronger the signal strength. Also, the use of an optional antenna will increase the effectiveness of your wireless communication. A simple wire will do the trick, with different antenna shapes and configurations based on the shape make of your project for best results.

			Relating code(transmitter)）：
			#include "DHT.h"
			#define DHTPIN 2
			#define DHTTYPE DHT11 // DHT 11
			DHT dht(DHTPIN, DHTTYPE);

			#include <VirtualWire.h>
			#undef int
			#undef abs
			#undef double
			#undef float
			#undef round
			char charnum[10];
			void setup() {
			Serial.begin(9600);
			Serial.println("setup");
			dht.begin();
			// Initialise the IO and ISR
			vw_set_ptt_inverted(true); // Required for DR3100
			vw_setup(2000); // Bits per sec
			}
			void loop() {

			int humidity = dht.readHumidity();
			int temp = dht.readTemperature();

			// check if returns are valid, if they are NaN (not a number) then something went wrong!
			if (isnan(humidity) \|\| isnan(temp)) {
			Serial.println("Failed to read from DHT");
			}
			else {
			char buff[30];
			sprintf(buff,"%c",255);
			const char *msg0 = buff;
			vw_send((uint8_t *)msg0, strlen(msg0)); // Send control character
			vw_wait_tx(); // Wait until the whole message is gone
			sprintf(buff,"%d",temp);
			const char *msg1 = buff;
			vw_send((uint8_t *)msg1, strlen(msg1)); // Send control character
			vw_wait_tx(); // Wait until the whole message is gone
			sprintf(buff,"%cC ",223);
			const char *msg2 = buff;
			vw_send((uint8_t *)msg2, strlen(msg2));
			vw_wait_tx(); // Wait until the whole message is gone
			sprintf(buff,"%c",254);
			const char *msg3 = buff;
			vw_send((uint8_t *)msg3, strlen(msg3));
			vw_wait_tx();
			sprintf(buff,"%d",humidity);
			const char *msg4 = buff;
			vw_send((uint8_t *)msg4, strlen(msg4)); // Send control character
			vw_wait_tx(); // Wait until the whole message is gone
			const char *msg5 = "% ";
			vw_send((uint8_t *)msg5, strlen(msg5));
			vw_wait_tx(); // Wait until the whole message is gone
			delay(1000);
			}
			}

			Receiver:

			#include <LCD4Bit_mod.h>
			LCD4Bit_mod lcd = LCD4Bit_mod(2);
			#include <VirtualWire.h>
			#undef int
			#undef abs
			#undef double
			#undef float
			#undef round
			void setup()
			{
			lcd.init();
			Serial.begin(9600); // Debugging only
			Serial.println("setup");

			// Initialise the IO and ISR
			vw_set_ptt_inverted(true); // Required for DR3100
			vw_setup(2000); // Bits per sec
			vw_set_rx_pin(23);
			vw_rx_start(); // Start the receiver PLL running
			}

			void loop()
			{

			uint8_t buf[VW_MAX_MESSAGE_LEN];
			uint8_t buflen = VW_MAX_MESSAGE_LEN;

			if (vw_get_message(buf, &buflen)) // Non-blocking
			{
			int i;

			digitalWrite(13, true); // Flash a light to show received good message
			// Message with a good checksum received, dump it.
			Serial.print("Got: ");

			for (i = 0; i < buflen; i++)
			{
			if (buf[i]==255){ lcd.cursorTo(1,0);
			}

			lcd.print(buf[i]);
			}
			}
			}

Admin at 06:21, 5 April 2012

2012-04-05T06:21:22Z

← Older revision		Revision as of 06:21, 5 April 2012
Line 7:		Line 7:
	*[http://www.geeetech.com/arduino-uno-328-p-173.html Arduino Uno] ( this will be the transmitter with DHT11 sensor attached)		*[http://www.geeetech.com/arduino-uno-328-p-173.html Arduino Uno] ( this will be the transmitter with DHT11 sensor attached)
	*[http://www.geeetech.com/arduino-io-expansionxbeebluetoothsrs485-shield-p-232.html Arduino IO Expansion Shield]		*[http://www.geeetech.com/arduino-io-expansionxbeebluetoothsrs485-shield-p-232.html Arduino IO Expansion Shield]
	*[DHT11 Temparature & Humidity Sensor]		*[http://www.geeetech.com/dht11-temperature-and-r-humidity-breakout-p-425.html DHT11 Temparature & Humidity Sensor]
	*[http://www.geeetech.com/arduino-mega-2560-p-174.html Arduino Mega] (this will be the Receiver with LCD display attached)		*[http://www.geeetech.com/arduino-mega-2560-p-174.html Arduino Mega] (this will be the Receiver with LCD display attached)
	*[http://www.geeetech.com/arduino-lcd-1602-keypad-shield-p-251.html 16X2 LCD keypad shield]		*[http://www.geeetech.com/arduino-lcd-1602-keypad-shield-p-251.html 16X2 LCD keypad shield]

Admin at 06:20, 5 April 2012

2012-04-05T06:20:57Z

← Older revision		Revision as of 06:20, 5 April 2012
Line 5:		Line 5:

	Basic requirement：		Basic requirement：
	*Arduino Uno ( this will be the transmitter with DHT11 sensor attached)		*[http://www.geeetech.com/arduino-uno-328-p-173.html Arduino Uno] ( this will be the transmitter with DHT11 sensor attached)
	*Arduino IO Expansion Shield		*[http://www.geeetech.com/arduino-io-expansionxbeebluetoothsrs485-shield-p-232.html Arduino IO Expansion Shield]
	*DHT11 Temparature & Humidity Sensor		*[DHT11 Temparature & Humidity Sensor]
	*Arduino Mega (this will be the Receiver with LCD display attached)		*[http://www.geeetech.com/arduino-mega-2560-p-174.html Arduino Mega] (this will be the Receiver with LCD display attached)
	*16X2 LCD keypad shield		*[http://www.geeetech.com/arduino-lcd-1602-keypad-shield-p-251.html 16X2 LCD keypad shield]
	*433Mhz RF Transmitter		*[http://www.geeetech.com/433mhz-superheterodyne-3400-rf-link-kits-p-167.html 433Mhz RF Transmitter]
	*433Mhz RF Receiver		*[http://www.geeetech.com/433mhz-superheterodyne-3400-rf-link-kits-p-167.html 433Mhz RF Receiver]

	[[File:RF433a.jpg]]		[[File:RF433a.jpg]]

Admin at 06:18, 5 April 2012

2012-04-05T06:18:07Z

← Older revision		Revision as of 06:18, 5 April 2012
Line 5:		Line 5:

	Basic requirement：		Basic requirement：
	Arduino Uno ( this will be the transmitter with DHT11 sensor attached)		*Arduino Uno ( this will be the transmitter with DHT11 sensor attached)
	Arduino IO Expansion Shield		*Arduino IO Expansion Shield
	DHT11 Temparature & Humidity Sensor		*DHT11 Temparature & Humidity Sensor
	Arduino Mega (this will be the Receiver with LCD display attached)		*Arduino Mega (this will be the Receiver with LCD display attached)
	16X2 LCD keypad shield		*16X2 LCD keypad shield
	433Mhz RF Transmitter		*433Mhz RF Transmitter
	433Mhz RF Receiver		*433Mhz RF Receiver

	[[File:RF433a.jpg]]		[[File:RF433a.jpg]]

Admin at 06:17, 5 April 2012

2012-04-05T06:17:34Z

← Older revision		Revision as of 06:17, 5 April 2012
Line 36:		Line 36:

	[[File:Re station1.jpg\|500px]]		[[File:Re station1.jpg\|500px]]

	There are two methods for expanding the range and efficiency of these two devices. Each transmitter device has a supply voltage range of 2 – 12 volts. The higher the voltage, the stronger the signal strength. Also, the use of an optional antenna will increase the effectiveness of your wireless communication. A simple wire will do the trick, with different antenna shapes and configurations based on the shape make of your project for best results.		There are two methods for expanding the range and efficiency of these two devices. Each transmitter device has a supply voltage range of 2 – 12 volts. The higher the voltage, the stronger the signal strength. Also, the use of an optional antenna will increase the effectiveness of your wireless communication. A simple wire will do the trick, with different antenna shapes and configurations based on the shape make of your project for best results.

Admin at 06:17, 5 April 2012

2012-04-05T06:17:16Z

← Older revision		Revision as of 06:17, 5 April 2012
Line 14:		Line 14:

	[[File:RF433a.jpg]]		[[File:RF433a.jpg]]

	First of all, let’s get a tough idea of RF module and how it works. Comparing with Xbee, RF module is the cost-effective wireless device for remote control and data transmission, as the name suggests, the RF module operates at Radio Frequency. The corresponding frequency range varies between 30 kHz & 300 GHz. In this RF system, the digital data is represented as variations in the amplitude of carrier wave. This kind of modulation is known as Amplitude Shift Keying (ASK).		First of all, let’s get a tough idea of RF module and how it works. Comparing with Xbee, RF module is the cost-effective wireless device for remote control and data transmission, as the name suggests, the RF module operates at Radio Frequency. The corresponding frequency range varies between 30 kHz & 300 GHz. In this RF system, the digital data is represented as variations in the amplitude of carrier wave. This kind of modulation is known as Amplitude Shift Keying (ASK).

Line 20:		Line 21:
	Transmitter Station:		Transmitter Station:

	[[File:Tr station.jpg]]		[[File:Tr station.jpg\|500px]]

	DHT11 sensor is basic and cheap device for hobbyists who want to do some data logging, which is good for 0-50C temperature and 20-80% humidity with 2-5% accuracy. Pin S on the DH11 breakout is connected to Arduino Uno pin 2. More details and DHT11 library please visit previous blog and wiki page.		DHT11 sensor is basic and cheap device for hobbyists who want to do some data logging, which is good for 0-50C temperature and 20-80% humidity with 2-5% accuracy. Pin S on the DH11 breakout is connected to Arduino Uno pin 2. More details and DHT11 library please visit previous blog and wiki page.
Line 28:		Line 29:
	Receiver Station:		Receiver Station:

	[[File:Re station.jpg]]		[[File:Re station.jpg\|500px]]

	The LCD Keypad shield is developed for Arduino compatible boards, to provide a user-friendly interface that allows users to go through the menu, make selections etc. It consists of a 1602 LCD. The keypad consists of 5 keys — select, up, right, down and left. LCD4Bit_mod library needs to be installed for this LCD keypad.		The LCD Keypad shield is developed for Arduino compatible boards, to provide a user-friendly interface that allows users to go through the menu, make selections etc. It consists of a 1602 LCD. The keypad consists of 5 keys — select, up, right, down and left. LCD4Bit_mod library needs to be installed for this LCD keypad.
Line 34:		Line 35:
	Data pin on the RF receiver module is connected to digital pin11 on Arduino by default for receiving data. As a result of mounting the LCD keypad shield, all of the space available is occupied on Uno, on Arduino Mega, the default data receiving pin 11 on Mega is also covered by LCD shield’s considerable bulk. The defualt pin needs to be modified for digital pin22 using vw_set_rx_pin() function.		Data pin on the RF receiver module is connected to digital pin11 on Arduino by default for receiving data. As a result of mounting the LCD keypad shield, all of the space available is occupied on Uno, on Arduino Mega, the default data receiving pin 11 on Mega is also covered by LCD shield’s considerable bulk. The defualt pin needs to be modified for digital pin22 using vw_set_rx_pin() function.

	[[File:Re station1.jpg]]		[[File:Re station1.jpg\|500px]]
	There are two methods for expanding the range and efficiency of these two devices. Each transmitter device has a supply voltage range of 2 – 12 volts. The higher the voltage, the stronger the signal strength. Also, the use of an optional antenna will increase the effectiveness of your wireless communication. A simple wire will do the trick, with different antenna shapes and configurations based on the shape make of your project for best results.		There are two methods for expanding the range and efficiency of these two devices. Each transmitter device has a supply voltage range of 2 – 12 volts. The higher the voltage, the stronger the signal strength. Also, the use of an optional antenna will increase the effectiveness of your wireless communication. A simple wire will do the trick, with different antenna shapes and configurations based on the shape make of your project for best results.