| // I2C SRF10 or SRF08 Devantech Ultrasonic Ranger Finder |
| // by Nicholas Zambetti <http://www.zambetti.com> |
| // and James Tichenor <http://www.jamestichenor.net> |
| |
| // Demonstrates use of the Wire library reading data from the |
| // Devantech Utrasonic Rangers SFR08 and SFR10 |
| |
| // Created 29 April 2006 |
| |
| // This example code is in the public domain. |
| |
| |
| #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(112); // transmit to device #112 (0x70) |
| // the address specified in the datasheet is 224 (0xE0) |
| // but i2c adressing uses the high 7 bits so it's 112 |
| 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(70); // datasheet suggests at least 65 milliseconds |
| |
| // step 3: instruct sensor to return a particular echo reading |
| Wire.beginTransmission(112); // transmit to device #112 |
| Wire.write(byte(0x02)); // sets register pointer to echo #1 register (0x02) |
| Wire.endTransmission(); // stop transmitting |
| |
| // step 4: request reading from sensor |
| Wire.requestFrom(112, 2); // request 2 bytes from slave device #112 |
| |
| // 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 :) |
| } |
| |
| |
| /* |
| |
| // The following code changes the address of a Devantech Ultrasonic Range Finder (SRF10 or SRF08) |
| // usage: changeAddress(0x70, 0xE6); |
| |
| void changeAddress(byte oldAddress, byte newAddress) |
| { |
| Wire.beginTransmission(oldAddress); |
| Wire.write(byte(0x00)); |
| Wire.write(byte(0xA0)); |
| Wire.endTransmission(); |
| |
| Wire.beginTransmission(oldAddress); |
| Wire.write(byte(0x00)); |
| Wire.write(byte(0xAA)); |
| Wire.endTransmission(); |
| |
| Wire.beginTransmission(oldAddress); |
| Wire.write(byte(0x00)); |
| Wire.write(byte(0xA5)); |
| Wire.endTransmission(); |
| |
| Wire.beginTransmission(oldAddress); |
| Wire.write(byte(0x00)); |
| Wire.write(newAddress); |
| Wire.endTransmission(); |
| } |
| |
| */ |