more rp2040 stuff

extensions/platformio/HX711_read/src/main.cpp

@@ -0,0 +1,84 @@
+#include <Arduino.h>
+#include "HX711.h"
+
+const int LOADCELL_DOUT_PIN = 2;
+const int LOADCELL_SCK_PIN = 3;
+
+HX711 scale;
+
+float smoothedWeight = 0.0;
+float alpha = 0.3; 
+float calibration_factor = 111.17; 
+float known_weight = 796.0; 
+
+// Stability Lock Variables
+float lastDisplayedWeight = 0.0;
+const float STABILITY_THRESHOLD = 0.5;
+
+void calibrateScale() {
+    Serial.println("--- Calibration Mode ---");
+    Serial.println("1. Clear scale, type 't' to tare.");
+    Serial.print("2. Place "); Serial.print(known_weight); Serial.println("g weight.");
+    Serial.println("3. Type 'c' to confirm weight.");
+    
+    while (true) {
+        if (Serial.available()) {
+            char c = Serial.read();
+            if (c == 't') {
+                scale.tare();
+                Serial.println("Tared! Place weight and type 'c'...");
+            } else if (c == 'c') {
+                long reading = scale.get_value(15); 
+                calibration_factor = (float)reading / known_weight;
+                scale.set_scale(calibration_factor);
+                Serial.print("New Factor: "); Serial.println(calibration_factor);
+                Serial.println("Calibration Done! Exiting mode.");
+                break;
+            }
+        }
+    }
+}
+
+void setup() {
+    Serial.begin(115200);
+    scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
+    scale.set_gain(128); 
+    scale.set_scale(calibration_factor);
+    scale.tare();
+    Serial.println("HX711 Ready (Stable Lock Mode)");
+}
+
+void loop() {
+    if (scale.is_ready()) {
+        float currentReading = scale.get_units(1);
+        smoothedWeight = (alpha * currentReading) + (1.0 - alpha) * smoothedWeight;
+
+        // 1. Calculate the intended new display value
+        float targetWeight = round(smoothedWeight * 2.0) / 2.0;
+        if (abs(targetWeight) < 1.0) targetWeight = 0.0;
+
+        // 2. Stability Check
+        // Only update lastDisplayedWeight if the change exceeds the threshold
+        if (abs(targetWeight - lastDisplayedWeight) >= STABILITY_THRESHOLD) {
+            lastDisplayedWeight = targetWeight;
+        }
+
+        Serial.print("Weight: ");
+        Serial.print(lastDisplayedWeight, 1);
+        Serial.println(" g");
+    }
+
+    if (Serial.available()) {
+        char cmd = Serial.read();
+        if (cmd == 't') {
+            scale.tare();
+            smoothedWeight = 0; 
+            lastDisplayedWeight = 0; // Force display to zero immediately
+            Serial.println(">> Tared");
+        } else if (cmd == 'k') {
+            calibrateScale();
+        }
+    }
+
+    delay(10); 
+}