Add option to invert power values in ECH1560

code/espurna/config/general.h

@@ -598,6 +598,9 @@ PROGMEM const char* const custom_reset_string[] = {
     #ifndef ECH1560_MISO_PIN
     #define ECH1560_MISO_PIN            5
     #endif
+    #ifndef ECH1560_INVERTED
+    #define ECH1560_INVERTED            0
+    #endif
 
     #define ECH1560_SYNC_INTERVAL       600
     #define ECH1560_BAUDRATE            4800

code/espurna/config/hardware.h

@@ -879,6 +879,7 @@
     #define POWER_PROVIDER      POWER_PROVIDER_ECH1560
     #define ECH1560_CLK_PIN     4
     #define ECH1560_MISO_PIN    5
+    #define ECH1560_INVERTED    0
 
 // -----------------------------------------------------------------------------
 // Unknown hardware

code/espurna/power_ech1560.ino

@@ -97,6 +97,12 @@ void _ech1560_sync() {
             }
         }
 
+        #if ECH1560_INVERTED
+            byte1 = 255 - byte1;
+            byte2 = 255 - byte2;
+            byte3 = 255 - byte3;
+        #endif
+
         // power = (Ba*255+Bb+Bc/255)/2
         _ech1560_apparent = ( (float) byte1 * 255 + (float) byte2 + (float) byte3 / 255.0) / 2;
         _ech1560_current = _ech1560_apparent / _ech1560_voltage;