Today I worked more on the Ultrasonic sensor programming. It works with sensing if the hopper is full now. I removed the coding that shows that the hopper is filling on the LCD display since it was pretty unnecessary. I also started to work on the programming for the compass, but I am temporarily using the Hitachi HM55B Compass Module since we are ultimately using the Pololu LSM303D Compass Module. I found example code to get data off of the Compass Module and display it.
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| Displays current reading and hopper status |
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| Readings of the HM55B Compass Module |
Ultrasonic Program
#include <SoftwareSerial.h>
#include <Timer.h>
const int TxPin = 18;
const int pingPin = 30;
int counter = 0;
SoftwareSerial mySerial = SoftwareSerial(255, TxPin);
void setup()
{
Serial.begin(9600); // initialize serial communication:
}
void loop()
{
long duration, inches, cm; // establish variables for duration of the ping,
// and the distance result in inches and centimeters:
pinMode(TxPin, OUTPUT);
digitalWrite(TxPin, HIGH);
mySerial.begin(9600);
delay(50);
mySerial.write(12); // Clear
mySerial.write(17); // Turn backlight on
delay(5); // Required delay
pinMode(pingPin, OUTPUT); // The PING))) is triggered by a HIGH pulse of 2 or more microseconds.
digitalWrite(pingPin, LOW); // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
delayMicroseconds(2);
digitalWrite(pingPin, HIGH);
delayMicroseconds(5);
digitalWrite(pingPin, LOW);
pinMode(pingPin, INPUT); // The same pin is used to read the signal from the PING))): a HIGH
duration = pulseIn(pingPin, HIGH); // pulse whose duration is the time (in microseconds) from the sending
// of the ping to the reception of its echo off of an object.
inches = microsecondsToInches(duration); // convert the time into a distance
cm = microsecondsToCentimeters(duration);
mySerial.print(inches);
mySerial.print("in, ");
mySerial.print(cm);
mySerial.print("cm");
mySerial.println();
delay(5);
if(counter > 10)
{
mySerial.write(13); // Turn backlight on
mySerial.write(12); // Clear screen
mySerial.print("Hopper Full");
}
else
{
mySerial.write(13); // Turn backlight on
mySerial.print("Empty");
}
if(inches < 4)
{
counter++;
}
else
{
counter=0;
}
}
long microsecondsToInches(long microseconds)
{
// According to Parallax's datasheet for the PING))), there are
// 73.746 microseconds per inch (i.e. sound travels at 1130 feet per
// second). This gives the distance travelled by the ping, outbound
// and return, so we divide by 2 to get the distance of the obstacle.
return microseconds / 74 / 2;
}
long microsecondsToCentimeters(long microseconds)
{
// The speed of sound is 340 m/s or 29 microseconds per centimeter.
// The ping travels out and back, so to find the distance of the
// object we take half of the distance travelled.
return microseconds / 29 / 2;
}
Compass Program
#include <math.h>
//// VARS
byte CLK_pin = 8;
byte EN_pin = 9;
byte DIO_pin = 10;
int X_Data = 0;
int Y_Data = 0;
int angle;
//// FUNCTIONS
void ShiftOut(int Value, int BitsCount) {
for(int i = BitsCount; i >= 0; i--) {
digitalWrite(CLK_pin, LOW);
if ((Value & 1 << i) == ( 1 << i)) {
digitalWrite(DIO_pin, HIGH);
}
else {
digitalWrite(DIO_pin, LOW);
}
digitalWrite(CLK_pin, HIGH);
delayMicroseconds(1);
}
}
int ShiftIn(int BitsCount) {
int ShiftIn_result;
ShiftIn_result = 0;
pinMode(DIO_pin, INPUT);
for(int i = BitsCount; i >= 0; i--) {
digitalWrite(CLK_pin, HIGH);
delayMicroseconds(1);
if (digitalRead(DIO_pin) == HIGH) {
ShiftIn_result = (ShiftIn_result << 1) + 1;
}
else {
ShiftIn_result = (ShiftIn_result << 1) + 0;
}
digitalWrite(CLK_pin, LOW);
delayMicroseconds(1);
}
// below is difficult to understand:
// if bit 11 is Set the value is negative
// the representation of negative values you
// have to add B11111000 in the upper Byte of
// the integer.
if ((ShiftIn_result & 1 << 11) == 1 << 11) {
ShiftIn_result = (B11111000 << 8) | ShiftIn_result;
}
return ShiftIn_result;
}
void HM55B_Reset() {
pinMode(DIO_pin, OUTPUT);
digitalWrite(EN_pin, LOW);
ShiftOut(B0000, 3);
digitalWrite(EN_pin, HIGH);
}
void HM55B_StartMeasurementCommand() {
pinMode(DIO_pin, OUTPUT);
digitalWrite(EN_pin, LOW);
ShiftOut(B1000, 3);
digitalWrite(EN_pin, HIGH);
}
int HM55B_ReadCommand() {
int result = 0;
pinMode(DIO_pin, OUTPUT);
digitalWrite(EN_pin, LOW);
ShiftOut(B1100, 3);
result = ShiftIn(3);
return result;
}
void setup() {
Serial.begin(9600);
pinMode(EN_pin, OUTPUT);
pinMode(CLK_pin, OUTPUT);
pinMode(DIO_pin, INPUT);
HM55B_Reset();
}
void loop() {
HM55B_StartMeasurementCommand(); // necessary!!
delay(40); // the data is 40ms later ready
Serial.print(HM55B_ReadCommand()); // read data and print Status
Serial.print(" ");
X_Data = ShiftIn(11); // Field strength in X
Y_Data = ShiftIn(11); // and Y direction
//Serial.print(X_Data); // print X strength
//Serial.print(" ");
//Serial.print(Y_Data); // print Y strength
//Serial.print(" ");
digitalWrite(EN_pin, HIGH); // ok deselect chip
angle = 180 * (atan2(-1 * Y_Data , X_Data) / M_PI); // angle is atan( -y/x) !!!
Serial.print("angle = ");
Serial.print(angle); // print angle
Serial.println();
//Serial.println("");
}
