Hi everybody,
I am trying to read dissolved oxygen from the Atlas Scientific sensor.datasheet is given here
https://www.atlas-scientific.com/_files … asheet.pdf?
My code for reading is as under:
#include <Wire.h>
void setup() {
Wire.begin(); // join i2c bus (address optional for master)
Serial.begin(9600); // start serial communication at 9600bps
}
int reading = 0;
void loop() {
// step 1: instruct sensor to read echoes
Wire.beginTransmission(97); // transmit to device #97(0x70)
// the address specified in the datasheet is 224 (0xE0)
// but i2c adressing uses the high 7 bits so it’s 97
Wire.write(byte(0x00)); // sets register pointer to the command register (0x00)
Wire.write(byte(0x50)); // command sensor to measure in “inches” (0x50)
// use 0x51 for centimeters
// use 0x52 for ping microseconds
Wire.endTransmission(); // stop transmitting
// step 2: wait for readings to happen
delay(700); // datasheet suggests at least 65 milliseconds
// step 3: instruct sensor to return a particular echo reading
Wire.beginTransmission(97); // transmit to device #97
Wire.write(byte(0x02)); // sets register pointer to echo #1 register (0x02)
Wire.endTransmission(); // stop transmitting
// step 4: request reading from sensor
Wire.requestFrom(97, 2); // request 2 bytes from slave device #97
// step 5: receive reading from sensor
if (2 <= Wire.available()) { // if two bytes were received
reading = Wire.read(); // receive high byte (overwrites previous reading)
reading = reading << 8; // shift high byte to be high 8 bits
reading |= Wire.read(); // receive low byte as lower 8 bits
Serial.println(reading); // print the reading
}
delay(250); // wait a bit since people have to read the output 
}
But im not able to read in the serial monitor and the response is pasted here as :
requestFrom: readed=0, quantity=2 : ERROR
requestFrom: readed=0, quantity=2 : ERROR
Can you please guide where is the mistake ? thanking a lot in advance.