From 02e2fb71cda0746e6c19c45e81f9ff42cd92f754 Mon Sep 17 00:00:00 2001
From: Yohan Boujon <yo.boujon@gmail.com>
Date: Tue, 3 Dec 2024 16:23:40 +0100
Subject: [PATCH] Updated sensor.

---
 lib/sensor/sensor.cpp | 22 ++++++++++------------
 lib/sensor/sensor.hpp |  6 ++++--
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/sensor/sensor.cpp b/lib/sensor/sensor.cpp
index cc8af8b..936aaad 100644
--- a/lib/sensor/sensor.cpp
+++ b/lib/sensor/sensor.cpp
@@ -11,17 +11,15 @@ void Sensor::init(const uint8_t pin)
     digitalWrite(_pin, HIGH);
 }
 
-float Sensor::get_value()
+float Sensor::get_analog()
 {
-    /*
-    float sensor_volt;
-    float RS_gas; // Get value of RS in a GAS
-    float ratio; // Get ratio RS_GAS/RS_air
-    int sensorValue = analogRead(A0);
-    sensor_volt=(float)sensorValue/1024*5.0;
-    RS_gas = (5.0-sensor_volt)/sensor_volt; // omit *RL
-    //-Replace the name "R0" with the value of R0 in the demo of First Test 
-    ratio = RS_gas/R0;  // ratio = RS/R0
-    */
-    return ((analogRead(_pin))/1024*5.0);
+    return analogRead(_pin);
+}
+
+// Normally should be 5V, but the ADC can only see up to 3.3 on 12 bits
+float Sensor::get_RSR0()
+{
+    float sensor_volt=(float)(analogRead(_pin))/((1<<12)*3.3);
+    float RS_gas = (3.3-sensor_volt)/sensor_volt;
+    return RS_gas/R0;
 }
\ No newline at end of file
diff --git a/lib/sensor/sensor.hpp b/lib/sensor/sensor.hpp
index 23d0426..d4d356a 100644
--- a/lib/sensor/sensor.hpp
+++ b/lib/sensor/sensor.hpp
@@ -3,13 +3,15 @@
 
 #include <Arduino.h>
 
-constexpr uint8_t SENSOR_PIN = 36;
+constexpr uint8_t SENSOR_PIN = 34;
+constexpr float R0 = 0.8;
 
 class Sensor {
 public:
     Sensor();
     void init(const uint8_t pin);
-    float get_value();
+    float get_analog();
+    float get_RSR0();
 private:
     uint8_t _pin;
 };