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--- hall_sensor [2025/11/02 21:08] – 46.109.187.144
+++ hall_sensor [2025/11/02 21:21] (current) – [Savienojum] 46.109.187.144
@@ Line 4: / Line 4: @@
 </WRAP>
-===== PINS =====
+===== Savienojum=====
+  - {{pasted:20251102-211157.png}}
+  - {{pasted:20251102-211751.png}}
+  - Mūsu gadījumā izveidot USB savienojums ērtākai konstrukcijai
+  - USB pins {{pasted:20251102-212034.png}}
+  - Dotā gadījuma USB dati saslēgti ar D+ kontaktu
+===== ARDUINO PINS =====
+  * PIN2
+  * GND
+  * 5V
+===== ARDUINO CODE =====
+<code>
+// Hall sensor wheel speed calculator (auto-zero)
+// Arduino MKR NB 1500 + NJK-5002C
+// 7 cm radius, 4 magnets = 0.10996 m per pulse
+const int sensorPin = 2;
+const int ledPin = LED_BUILTIN;
+const float pulseDistance = 0.10996;  // meters per magnet pulse
+unsigned long lastDetectTime = 0;
+unsigned long lastPrint = 0;
+float speed_kmh = 0.0;
+int lastState = HIGH;
+void setup() {
+  Serial.begin(9600);
+  pinMode(sensorPin, INPUT_PULLUP);
+  pinMode(ledPin, OUTPUT);
+  Serial.println("Wheel speed calculation running...");
+}
+void loop() {
+  int state = digitalRead(sensorPin);
+  // detect magnet arrival edge (HIGH → LOW)
+  if (lastState == HIGH && state == LOW) {
+    unsigned long now = millis();
+    if (lastDetectTime > 0) {
+      unsigned long delta = now - lastDetectTime; // time between pulses (ms)
+      float delta_s = delta / 1000.0;             // convert to seconds
+      float speed_mps = pulseDistance / delta_s;  // m/s
+      speed_kmh = speed_mps * 3.6;                // km/h
+    }
+    lastDetectTime = now;
+    digitalWrite(ledPin, HIGH); // blink LED when detected
+  }
+  // turn LED off shortly after detection
+  if (digitalRead(ledPin) == HIGH && (millis() - lastDetectTime > 50)) {
+    digitalWrite(ledPin, LOW);
+  }
+  // auto-zero speed if no pulse for 1 second
+  if (millis() - lastDetectTime > 1000) {
+    speed_kmh = 0.0;
+  }
+  // print speed every 0.5 s
+  if (millis() - lastPrint > 500) {
+    lastPrint = millis();
+    Serial.print("Speed: ");
+    Serial.print(speed_kmh, 2);
+    Serial.println(" km/h");
+  }
+  lastState = state;
+}
+</code>