12. Input Devices – Group Kuriyama¶
This is group assignment page of Computer-controlled cutting (Kuriyama Student) :
Group assignment¶
- Probe an input device’s analog levels and digital signals
What we’ve done this week¶
- Probe an input device’s digital signals (Atsufumi Suzuki)
Probe HC-SR04 (Ultra sonic sensor)
- 5V Supply
- Trigger Pulse Input
- Echo Pulse Output
- 0V Ground
Electric Parameter¶
Electric Parameter | parameter |
---|---|
Working Voltage | DC 5 V |
Working Current | 15mA |
Working Frequency | 40Hz |
Max Range | 4m |
Min Range | 2cm |
MeasuringAngle | 15 degree |
Trigger Input Signal | 10uS TTL pulse |
Echo Output Signal | Input TTL lever signal and the range in proportion |
Dimension | 45 x 20 x 15mm |
First, I used an oscilloscope to measure the pulse waveforms on the trig and Echo pins.
Program¶
const int TRIG_PIN = 0;
const int ECHO_PIN = 1;
float duration_us, distance_cm;
void setup() {
Serial.begin (9600);
pinMode(TRIG_PIN, OUTPUT);
pinMode(ECHO_PIN, INPUT);
servo.attach(SERVO_PIN);
servo.write(0);
}
void loop() {
digitalWrite(TRIG_PIN, HIGH);
delayMicroseconds(10);
digitalWrite(TRIG_PIN, LOW);
duration_us = pulseIn(ECHO_PIN, HIGH);
distance_cm = 0.017 * duration_us;
Serial.print("distance: ");
Serial.print(distance_cm);
Serial.println(" cm");
delay(500);
}
In the void loop, the triger pin is changed from high (5v) to low (0v) at 10ms intervals.
digitalWrite(TRIG_PIN, HIGH);
delayMicroseconds(10);
digitalWrite(TRIG_PIN, LOW);
The following was confirmed by oscilloscope.
Photoresistor¶
I connect with photoresistor.
and check the wave of signal.
You can see constantly taking the analog signal.
Links to Files and Code¶
Appendix¶
Last update:
May 1, 2022