[136] | 1 | // I2C SRF10 or SRF08 Devantech Ultrasonic Ranger Finder
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| 2 | // by Nicholas Zambetti <http://www.zambetti.com>
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| 3 | // and James Tichenor <http://www.jamestichenor.net>
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| 4 |
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| 5 | // Demonstrates use of the Wire library reading data from the
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| 6 | // Devantech Utrasonic Rangers SFR08 and SFR10
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| 7 |
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| 8 | // Created 29 April 2006
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| 9 |
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| 10 | // This example code is in the public domain.
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| 11 |
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| 12 |
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| 13 | #include <Wire.h>
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| 14 |
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| 15 | void setup()
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| 16 | {
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| 17 | Wire.begin(); // join i2c bus (address optional for master)
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| 18 | Serial.begin(9600); // start serial communication at 9600bps
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| 19 | }
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| 20 |
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| 21 | int reading = 0;
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| 22 |
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| 23 | void loop()
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| 24 | {
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| 25 | // step 1: instruct sensor to read echoes
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| 26 | Wire.beginTransmission(112); // transmit to device #112 (0x70)
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| 27 | // the address specified in the datasheet is 224 (0xE0)
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| 28 | // but i2c adressing uses the high 7 bits so it's 112
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| 29 | Wire.write(byte(0x00)); // sets register pointer to the command register (0x00)
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| 30 | Wire.write(byte(0x50)); // command sensor to measure in "inches" (0x50)
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| 31 | // use 0x51 for centimeters
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| 32 | // use 0x52 for ping microseconds
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| 33 | Wire.endTransmission(); // stop transmitting
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| 34 |
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| 35 | // step 2: wait for readings to happen
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| 36 | delay(70); // datasheet suggests at least 65 milliseconds
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| 37 |
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| 38 | // step 3: instruct sensor to return a particular echo reading
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| 39 | Wire.beginTransmission(112); // transmit to device #112
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| 40 | Wire.write(byte(0x02)); // sets register pointer to echo #1 register (0x02)
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| 41 | Wire.endTransmission(); // stop transmitting
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| 42 |
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| 43 | // step 4: request reading from sensor
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| 44 | Wire.requestFrom(112, 2); // request 2 bytes from slave device #112
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| 45 |
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| 46 | // step 5: receive reading from sensor
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| 47 | if(2 <= Wire.available()) // if two bytes were received
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| 48 | {
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| 49 | reading = Wire.read(); // receive high byte (overwrites previous reading)
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| 50 | reading = reading << 8; // shift high byte to be high 8 bits
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| 51 | reading |= Wire.read(); // receive low byte as lower 8 bits
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| 52 | Serial.println(reading); // print the reading
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| 53 | }
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| 54 |
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| 55 | delay(250); // wait a bit since people have to read the output :)
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| 56 | }
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| 57 |
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| 58 |
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| 59 | /*
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| 60 |
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| 61 | // The following code changes the address of a Devantech Ultrasonic Range Finder (SRF10 or SRF08)
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| 62 | // usage: changeAddress(0x70, 0xE6);
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| 63 |
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| 64 | void changeAddress(byte oldAddress, byte newAddress)
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| 65 | {
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| 66 | Wire.beginTransmission(oldAddress);
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| 67 | Wire.write(byte(0x00));
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| 68 | Wire.write(byte(0xA0));
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| 69 | Wire.endTransmission();
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| 70 |
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| 71 | Wire.beginTransmission(oldAddress);
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| 72 | Wire.write(byte(0x00));
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| 73 | Wire.write(byte(0xAA));
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| 74 | Wire.endTransmission();
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| 75 |
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| 76 | Wire.beginTransmission(oldAddress);
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| 77 | Wire.write(byte(0x00));
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| 78 | Wire.write(byte(0xA5));
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| 79 | Wire.endTransmission();
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| 80 |
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| 81 | Wire.beginTransmission(oldAddress);
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| 82 | Wire.write(byte(0x00));
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| 83 | Wire.write(newAddress);
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| 84 | Wire.endTransmission();
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| 85 | }
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| 86 |
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| 87 | */
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