ESP32: Fix ADC/battery sense logic (SlimeVR#310)

* ESP32: Fix ADC voltage readings * Forgot endif oops * Refactor a little bit * Fix spelling of 'resolution'
VOLCA2333 · Jan 19, 2024 · 35da44b · 35da44b
1 parent c26ec17
commit 35da44b
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Showing 2 changed files with 11 additions and 12 deletions.
diff --git a/src/batterymonitor.cpp b/src/batterymonitor.cpp
@@ -77,8 +77,11 @@ void BatteryMonitor::Loop()
                     }
                 }
             #endif
-            #if BATTERY_MONITOR == BAT_EXTERNAL
-                voltage = ((float)analogRead(PIN_BATTERY_LEVEL)) * batteryADCMultiplier;
+            #if ESP8266 && BATTERY_MONITOR == BAT_EXTERNAL
+                voltage = ((float)analogRead(PIN_BATTERY_LEVEL)) * ADCVoltageMax / ADCResolution * ADCMultiplier;
+            #endif
+            #if ESP32 && BATTERY_MONITOR == BAT_EXTERNAL
+                voltage = ((float)analogReadMilliVolts(PIN_BATTERY_LEVEL)) / 1000 * ADCMultiplier;
             #endif
             #if BATTERY_MONITOR == BAT_MCP3021 || BATTERY_MONITOR == BAT_INTERNAL_MCP3021
                 if (address > 0)
@@ -91,7 +94,7 @@ void BatteryMonitor::Loop()
                     if (status == 0)
                     {
                         float v = (((uint16_t)(MSB & 0x0F) << 6) | (uint16_t)(LSB >> 2));
-                        v *= batteryADCMultiplier;
+                        v *= ADCMultiplier;
                         voltage = (voltage > 0) ? min(voltage, v) : v;
                     }
                 }

diff --git a/src/batterymonitor.h b/src/batterymonitor.h
@@ -30,15 +30,11 @@
 #include "logging/Logger.h"
 
 #if ESP8266
-    #define ADCResulution 1023.0  // ESP8266 has 12bit ADC
+    #define ADCResolution 1023.0  // ESP8266 has 10bit ADC
     #define ADCVoltageMax 1.0     // ESP8266 input is 1.0 V = 1023.0
 #endif
-#if ESP32
-    #define ADCResulution 4095.0  // ESP32 has 12bit ADC
-    #define ADCVoltageMax 3.3     // ESP32 input is 3.3 V = 4095.0
-#endif
-#ifndef ADCResulution
-    #define ADCResulution 1023.0
+#ifndef ADCResolution
+    #define ADCResolution 1023.0
 #endif
 #ifndef ADCVoltageMax
     #define ADCVoltageMax 1.0
@@ -64,10 +60,10 @@
     // Diagramm:
     //   (Battery)--- [BATTERY_SHIELD_RESISTANCE] ---(INPUT_BOARD)---  [BATTERY_SHIELD_R2] ---(ESP_INPUT)--- [BATTERY_SHIELD_R1] --- (GND)
     // SlimeVR Board can handle max 5V > so analogRead of 5.0V input will result in 1023.0
-  #define batteryADCMultiplier ADCVoltageMax / ADCResulution * (BATTERY_SHIELD_R1 + BATTERY_SHIELD_R2 + BATTERY_SHIELD_RESISTANCE) / BATTERY_SHIELD_R1
+  #define ADCMultiplier (BATTERY_SHIELD_R1 + BATTERY_SHIELD_R2 + BATTERY_SHIELD_RESISTANCE) / BATTERY_SHIELD_R1
 #elif BATTERY_MONITOR == BAT_MCP3021 || BATTERY_MONITOR == BAT_INTERNAL_MCP3021
   // Default recommended resistors are 9.1k and 5.1k
-  #define batteryADCMultiplier 3.3 / 1023.0 * 14.2 / 9.1
+  #define ADCMultiplier 3.3 / 1023.0 * 14.2 / 9.1
 #endif
 
 class BatteryMonitor