Make register array volatile

src/main.cpp

@@ -8,7 +8,7 @@
 #include <avr/io.h>
 
 #define MAJOR_VERSION 12 // Needs to be updated if the compatibility will change with tc2-agent, tc2-firmware, or tc2-hat-controller
-#define MINOR_VERSION 5  // Update for just small bug fixes that doesn't cause compatibility issues with other software.
+#define MINOR_VERSION 6  // Update for just small bug fixes that doesn't cause compatibility issues with other software.
 
 //=====DEFINITIONS=====//
 #define BATTERY_HYSTERESIS 10
@@ -52,12 +52,11 @@
 #define POWER_OFF_RPI            0x01 << 3
 #define TOGGLE_AUX_TERMINAL_FLAG 0x01 << 4
 
-
-uint8_t registers[REG_LEN] = {0};
 uint8_t writeMasks[REG_LEN] = {}; // Should all be initialised to 0xFF
-uint8_t registerAddress = 0;
 
 //=====GLOBAL VARIABLES=====//
+volatile uint8_t registers[REG_LEN] = {0};
+volatile uint8_t registerAddress = 0;
 volatile uint16_t battLowVoltageDiv = 0;      // Raw reading value from ADC
 volatile uint16_t battHighVoltageDiv = 0;     // Raw reading value from ADC
 volatile uint16_t battRTC = 0;      // Raw reading value from ADC
@@ -217,7 +216,7 @@ void loop() {
 
   updateLEDs();
   //delay(50);
-  sleep_cpu();
+  sleep_mode();
 }
 
 void updateLEDs() {