Hello,
I have an application where I am using a MCP3421 18bit ADC to read analog data. The setup is Xbee+Xbee Sheild+Arduino + MCP3421 as Transmitter. This I am reading and transmitting to a remote xbee+arduino module with LCD. The data is displayed fine on the LCD. however I want to receive the data on the Serial port. When i try tp Do a Serial.println(s); on the receiving code the data which i get on serial port is garbled. Would appreciate any help
Here is my Code
Transmitting
#include <Wire.h>
#define TRUE 1
#define FALSE 0
void setup(void)
{
Serial.begin(9600);
Wire.begin();
delay(100);
Serial.println(">>>>>>>>>>>>>>>>>>>>>>>>"); // just to be sure things are working
}
void loop(void)
{
byte address, Hi, Lo, Config;
int ADVal;
while(1)
{
address = 0x68;
Wire.beginTransmission(address);
Wire.write(0x88); // config register %1000 1000
// /RDY = 1, One Conversion, 15 samples per, PGA = X1
Wire.endTransmission();
delay(1);
Wire.requestFrom((int)address, (int) 3);
Hi = Wire.read();
Lo = Wire.read();
Config = Wire.read();
Wire.endTransmission();
ADVal = Hi;
ADVal = ADVal * 256 + Lo;
Serial.print("<"); // Sending a marker for value start
Serial.print(ADVal);
Serial.print(">"); // sending a marker for value end
delay(10);
}
}
and this is the receiving code
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2); // initialize the library with the numbers of the interface pins
bool started = false;
bool ended= false;
char inData[10]; // Leave plenty of room
byte index;
float i;
//char inData[24]; // Or whatever size you need
//byte index = 0;
void setup(){
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// initialize the serial communications:
Serial.begin(9600);
}
void loop()
{
//Serial.println(s);
while(Serial.available() > 0)
{
char aChar = Serial.read();
if(aChar == '<')
{
// Start of packet marker read
index = 0;
inData[index] = '\0'; // Throw away any incomplete packet
started = true;
ended = false;
}
else if(aChar == '>')
{
// End of packet marker read
ended = true;
break; // Done reading serial data for now
}
else
{
if(index < 10) // Make sure there is room
{
inData[index] = aChar; // Add char to array
index++;
inData[index] = '\0'; // Add NULL to end
}
}
}
// When we get here, there is no more serial data to read,
// or we have read an end-of-packet marker
if(started && ended)
{
// We've seen both markers - do something with the data here
lcd.setCursor(0,0);
i = atoi (inData);
float s = (i * 0.3051851); //multiplying with calibration factor
float value = ( s / 1000 );
lcd.setCursor(1,0);
lcd.print(value,3); // print value after multiplying with calibration factor to LCD
lcd.setCursor(0,1 );
lcd.print(i); // Print raw ADC counts as recieved from transmitter
index = 0;
inData[index] = '\0';
started = false;
ended = false;
}
}
What I am doing here is reading the MCP3421 on I2C bus and transmitting the raw counts. with a start and end marker as This on recieving I am parsing to DATA enabling me to reject and incomplete data value .
Thanks
