Temperature sensor.
Now let me introduce to the integrated circuit DS1621, which is a thermometer with a communication system based on a I²C (Integrated-integrated communication)
Our cubieboard also has I²C connection, but I'm still working on a system to send the information from the senses (arduino) to the brain (cubieboard)
This is the video about the construction of all circuit.
I began, doing the circuit to work with the arduino, and checked.
I send the information to the serial, and show it on the screen
After that I connected the serial cable between the arduino y and cubieboard (the cable is an old cd-cable from my old computer)
Here is the video
and here is the result at the cubieboard
There are a lot of information about how to program the arduinos and I²C
I've changed the library "Protocol", cause it's not really necessary a port, cause in the case of I2C its possible to add few of integrated circuirt at the same ports, which will use the same channel of communications
a little bit of code
[CODE TO READ THE DS1621]
#include <Wire.h>
#include <protocol.h>
#define DEV_ID 0x90 >> 1
Protocol protocolTemperature("Temperature");
void setup()
{
Serial.begin(9600);//I'm using 9600 bps to comunicate the arduino and the cubieboard
Wire.begin();
Wire.beginTransmission(DEV_ID); //connect to DS1621
Wire.write(0xAC); //Access config
Wire.write(0x02);
Wire.beginTransmission(DEV_ID); //restart the DS1621
Wire.write(0xEE); // start conversion
//read the documentation its a very interesting temperature sensor
}
void loop()
{
protocolTemperature.send(readTemperature());
}
// This will go to another library
//I love the libraries :)
float readTemperature()
{
int8_t firstByte;
int8_t secondByte;
float temp = 0;
delay(1000); // give time for measurement
Wire.beginTransmission(DEV_ID);
Wire.write(0xAA); // read temperature command
Wire.endTransmission();
Wire.requestFrom(DEV_ID, 2); // request two bytes from DS1621 (0.5 deg. resolution)
firstByte = Wire.read(); // get first byte
secondByte = Wire.read(); // get second byte
temp = firstByte;
if (secondByte) // if there is a 0.5 deg difference
temp += 0.5;
return (temp);
}
[PROTOCOL.cpp]
void Protocol::send(float value)
{
char buffer[16];
//NOTE: HOW TO CONVERT A FLOAT TO STRING IN ARDUINO
dtostrf(value,5,2,buffer);
Serial.println(_id+":"+buffer);
}
[PROTOCOL.h]
//This class will be growing
class Protocol
{
public:
Protocol (String id);
String getId();
void send(String msg);
void send(float value);
private:
String _id;
};
The circuit to use I²C is quite simple
