diff --git a/include/arm11/hardware/hid.h b/include/arm11/hardware/hid.h
index ff10158..77e6110 100644
--- a/include/arm11/hardware/hid.h
+++ b/include/arm11/hardware/hid.h
@@ -66,13 +66,13 @@
 // Extra keys use with hidGetExtraKeys()
 enum
 {
-	KEY_POWER      = (1u<<0),
-	KEY_POWER_HELD = (1u<<1),
-	KEY_HOME       = (1u<<2), // Auto clear on release
-	KEY_WIFI       = (1u<<3),
-	KEY_SHELL      = (1u<<4), // Auto clear on open
-	KEY_CHARGER    = (1u<<5), // Auto clears on unplugging
-	KEY_VOL_SLIDER = (1u<<6)
+	KEY_POWER        = (1u<<0),
+	KEY_POWER_HELD   = (1u<<1),
+	KEY_HOME         = (1u<<2), // Auto clears on release
+	KEY_WIFI         = (1u<<3),
+	KEY_SHELL        = (1u<<4), // Auto clears on open
+	KEY_BAT_CHARGING = (1u<<5), // Auto clears when charging stops
+	KEY_VOL_SLIDER   = (1u<<6)
 };
 
 typedef struct
@@ -90,7 +90,6 @@
 
 
 void hidInit(void);
-bool hidIsHomeButtonHeldRaw(void);
 void hidScanInput(void);
 u32 hidKeysHeld(void);
 u32 hidKeysDown(void);
diff --git a/include/arm11/hardware/i2c.h b/include/arm11/hardware/i2c.h
index 5e1e104..0bb477a 100644
--- a/include/arm11/hardware/i2c.h
+++ b/include/arm11/hardware/i2c.h
@@ -33,9 +33,9 @@
 
 typedef enum
 {
-	I2C_DEV_POWER     = 0, 	// Unconfirmed
-	I2C_DEV_CAMERA    = 1, 	// Unconfirmed
-	I2C_DEV_CAMERA2   = 2, 	// Unconfirmed
+	I2C_DEV_POWER     = 0,  // Unconfirmed
+	I2C_DEV_CAMERA    = 1,  // Unconfirmed
+	I2C_DEV_CAMERA2   = 2,  // Unconfirmed
 	I2C_DEV_MCU       = 3,
 	I2C_DEV_GYRO      = 10,
 	I2C_DEV_DEBUG_PAD = 12,
diff --git a/include/arm11/hardware/mcu.h b/include/arm11/hardware/mcu.h
index d26e62f..f06a2e4 100644
--- a/include/arm11/hardware/mcu.h
+++ b/include/arm11/hardware/mcu.h
@@ -48,7 +48,7 @@
 void MCU_triggerPowerOff(void);
 void MCU_triggerReboot(void);
 u8 MCU_readBatteryLevel(void);
-bool MCU_readBatteryChargeState(void);
+u8 MCU_readExternalHwState(void);
 u8 MCU_readSystemModel(void);
 void MCU_readRTC(void *rtc);
 u32 MCU_readReceivedIrqs(void);
diff --git a/source/arm11/hardware/hid.c b/source/arm11/hardware/hid.c
index 2246e6a..ae490db 100644
--- a/source/arm11/hardware/hid.c
+++ b/source/arm11/hardware/hid.c
@@ -36,7 +36,7 @@
 static u32 extraKeys;
 //TouchPos tPos;
 //CpadPos cPos;
-static volatile bool mcuIrq = true;
+static volatile bool mcuIrq;
 
 
 
@@ -44,14 +44,19 @@
 
 void hidInit(void)
 {
-	extraKeys = kUp = kDown = kHeld = 0;
+	kUp = kDown = kHeld = 0;
+	mcuIrq = false;
 
-	// When set after a reboot from TWL_FIRM while holding the HOME button this will
-	// cause the MCU to spam IRQs infinitely after releasing the HOME button.
-	// mcuBugs++
-	// Update: For some reason this is not reproduceable anymore.
-	MCU_setIrqBitmask(0xFFBFFC80u);
+	(void)MCU_readReceivedIrqs();
+	u8 state = MCU_readExternalHwState();
+	u32 tmp = ~state<<3 & KEY_SHELL;      // Current shell state. Bit is inverted.
+	tmp |= state<<1 & KEY_BAT_CHARGING;   // Current battery charging state
+	state = MCU_readHidHeld();
+	tmp |= ~state<<1 & KEY_HOME;          // Current HOME button state
+	extraKeys = tmp;
+
 	IRQ_registerHandler(IRQ_MCU_HID, 14, 0, true, hidIrqHandler);
+	MCU_setIrqBitmask(0xFFBF3F80u);
 	GPIO_setBit(19, 9); // This enables the MCU IRQ.
 
 	//CODEC_init();
@@ -64,7 +69,6 @@
 
 static void updateMcuIrqState(void)
 {
-	// TODO: We should probably disable IRQs temporarily here.
 	if(!mcuIrq) return;
 	mcuIrq = false;
 
@@ -75,8 +79,8 @@
 	if(state & 1u<<3) tmp &= ~KEY_HOME;                     // HOME released
 	tmp |= state>>1 & (KEY_WIFI | KEY_SHELL);               // WiFi switch, shell closed
 	if(state & 1u<<6) tmp &= ~KEY_SHELL;                    // Shell opened
-	tmp |= state>>4 & KEY_CHARGER;                          // Charger plugged in
-	if(state & 1u<<8) tmp &= ~KEY_CHARGER;                  // Charger removed
+	tmp |= state>>10 & KEY_BAT_CHARGING;                    // Battery started charging
+	if(state & 1u<<14) tmp &= ~KEY_BAT_CHARGING;            // Battery stopped charging
 	tmp |= state>>16 & KEY_VOL_SLIDER;                      // Volume slider update
 	extraKeys = tmp;
 }
@@ -96,12 +100,12 @@
 	cPos.x = -(((buf[36]<<8 | buf[37]) & 0xFFFu) - 2048u); // X axis is inverted
 	cPos.y = ((buf[20]<<8 | buf[21]) & 0xFFFu) - 2048u;
 
-	if((cPos.x > 0 ? cPos.x : -cPos.x) > CPAD_THRESHOLD)
+	if((cPos.x >= 0 ? cPos.x : -cPos.x) > CPAD_THRESHOLD)
 	{
 		if(cPos.x >= 0) emuButtons |= KEY_CPAD_RIGHT;
 		else            emuButtons |= KEY_CPAD_LEFT;
 	}
-	if((cPos.y > 0 ? cPos.y : -cPos.y) > CPAD_THRESHOLD)
+	if((cPos.y >= 0 ? cPos.y : -cPos.y) > CPAD_THRESHOLD)
 	{
 		if(cPos.y >= 0) emuButtons |= KEY_CPAD_UP;
 		else            emuButtons |= KEY_CPAD_DOWN;
@@ -110,16 +114,11 @@
 	return emuButtons;
 }*/
 
-bool hidIsHomeButtonHeldRaw(void)
-{
-	return !(MCU_readHidHeld() & 1u<<1);
-}
-
 void hidScanInput(void)
 {
 	updateMcuIrqState();
 
-	u32 kOld = kHeld;
+	const u32 kOld = kHeld;
 	kHeld = /*rawCodec2Hid() |*/ REG_HID_PAD;
 	kDown = (~kOld) & kHeld;
 	kUp = kOld & (~kHeld);
@@ -152,7 +151,7 @@
 
 u32 hidGetExtraKeys(u32 clearMask)
 {
-	u32 tmp = extraKeys;
+	const u32 tmp = extraKeys;
 	extraKeys &= ~clearMask;
 
 	return tmp;
diff --git a/source/arm11/hardware/i2c.c b/source/arm11/hardware/i2c.c
index 0274dda..3e7def0 100644
--- a/source/arm11/hardware/i2c.c
+++ b/source/arm11/hardware/i2c.c
@@ -57,7 +57,7 @@
 	{I2C_BUS2, 0x2E},
 	{I2C_BUS2, 0x40},
 	{I2C_BUS2, 0x44},
-	{I2C_BUS3, 0xA6}, // TODO: Find out if 0xA6 or 0xD6 is correct
+	{I2C_BUS3, 0xD6},
 	{I2C_BUS3, 0xD0},
 	{I2C_BUS3, 0xD2},
 	{I2C_BUS3, 0xA4},
@@ -98,11 +98,9 @@
 
 void I2C_init(void)
 {
-	static bool initialized = false;
-	
-	/* run-once */
-	if(initialized) return;
-	initialized = true;
+	static bool inited = false;
+	if(inited) return;
+	inited = true;
 
 	IRQ_registerHandler(IRQ_I2C1, 14, 0, true, NULL);
 	IRQ_registerHandler(IRQ_I2C2, 14, 0, true, NULL);
@@ -175,9 +173,8 @@
 
 bool I2C_readRegBuf(I2cDevice devId, u8 regAddr, u8 *out, u32 size)
 {
-	const u8 busId = i2cDevTable[devId].busId;
 	const u8 devAddr = i2cDevTable[devId].devAddr;
-	I2cRegs *const regs = i2cGetBusRegsBase(busId);
+	I2cRegs *const regs = i2cGetBusRegsBase(i2cDevTable[devId].busId);
 
 
 	if(!i2cStartTransfer(devAddr, regAddr, true, regs)) return false;
@@ -199,9 +196,8 @@
 
 bool I2C_writeRegBuf(I2cDevice devId, u8 regAddr, const u8 *in, u32 size)
 {
-	const u8 busId = i2cDevTable[devId].busId;
 	const u8 devAddr = i2cDevTable[devId].devAddr;
-	I2cRegs *const regs = i2cGetBusRegsBase(busId);
+	I2cRegs *const regs = i2cGetBusRegsBase(i2cDevTable[devId].busId);
 
 
 	if(!i2cStartTransfer(devAddr, regAddr, false, regs)) return false;
@@ -245,9 +241,8 @@
 
 bool I2C_writeRegIntSafe(I2cDevice devId, u8 regAddr, u8 data)
 {
-	const u8 busId = i2cDevTable[devId].busId;
 	const u8 devAddr = i2cDevTable[devId].devAddr;
-	I2cRegs *const regs = i2cGetBusRegsBase(busId);
+	I2cRegs *const regs = i2cGetBusRegsBase(i2cDevTable[devId].busId);
 
 
 	u32 tries = 8;
diff --git a/source/arm11/hardware/mcu.c b/source/arm11/hardware/mcu.c
index 05e75e0..c552486 100644
--- a/source/arm11/hardware/mcu.c
+++ b/source/arm11/hardware/mcu.c
@@ -88,13 +88,9 @@
 	return state;
 }
 
-bool MCU_readBatteryChargeState(void)
+u8 MCU_readExternalHwState(void)
 {
-	u8 state;
-	
-	state = I2C_readReg(I2C_DEV_MCU, RegExHW);
-	
-	return (state & (1u << 4)) != 0;
+	return I2C_readReg(I2C_DEV_MCU, RegExHW);
 }
 
 u8 MCU_readSystemModel(void)
diff --git a/source/arm11/main.c b/source/arm11/main.c
index e88fade..3fb73f5 100644
--- a/source/arm11/main.c
+++ b/source/arm11/main.c
@@ -61,12 +61,12 @@
 	loadConfigFile();
 
 
+	hidScanInput();
 	// bootrom dumper?
 	// skip bootslot / FCRAM / reboot handling in that case
 	if(dump_bootroms)
 	{
-		// workaround when HOME button is held
-		if (hidIsHomeButtonHeldRaw())
+		if (hidGetExtraKeys(0) & KEY_HOME)
 		{
 			menu_ret = MENU_RET_REBOOT;
 			if (toggleSuperhax(false) == 0)
@@ -90,7 +90,7 @@
 	nextBootSlot = readStoredBootslot();
 	
 	// show menu if bootmode is normal or HOME button is pressed
-	show_menu = (!nextBootSlot && (bootmode == BootModeNormal)) || hidIsHomeButtonHeldRaw();
+	show_menu = (!nextBootSlot && (bootmode == BootModeNormal)) || hidGetExtraKeys(0) & KEY_HOME;
 	
 	// show splash if cold boot and (bootmode != BootModeQuiet)
 	bool splash_wait = false;
@@ -131,7 +131,6 @@
 	
 	
 	// check keys held at boot
-	hidScanInput();
 	u32 kHeld = hidKeysHeld();
 	
 	// boot slot keycombo held?
diff --git a/source/arm11/menu/battery.c b/source/arm11/menu/battery.c
index 40d3cb1..cb6b406 100644
--- a/source/arm11/menu/battery.c
+++ b/source/arm11/menu/battery.c
@@ -16,12 +16,14 @@
  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
  
-
-#include "arm11/hardware/mcu.h"
 #include "arm11/menu/battery.h"
+#include "arm11/hardware/mcu.h"
+#include "arm11/hardware/hid.h"
  
+
+
 void getBatteryState(BatteryState *battery)
 {
 	battery->percent = MCU_readBatteryLevel();
-	battery->charging = MCU_readBatteryChargeState();
+	battery->charging = hidGetExtraKeys(0) & KEY_BAT_CHARGING;
 }
diff --git a/source/arm11/start.s b/source/arm11/start.s
index edc814c..2c98a09 100644
--- a/source/arm11/start.s
+++ b/source/arm11/start.s
@@ -205,7 +205,7 @@
 	mov r0, #0
 	mov r1, #0xF00000           @ Give full access to cp10/11 in user and privileged mode
 	mov r2, #0x40000000         @ Clear exception bits and enable VFP11
-	mov r3, #0x3C00000          @ Round towards zero (RZ) mode, flush-to-zero mode, default NaN mode
+	mov r3, #0x3000000          @ Round to nearest (RN) mode, flush-to-zero mode, default NaN mode
 	mcr p15, 0, r1, c1, c0, 2   @ Write Coprocessor Access Control Register
 	mcr p15, 0, r0, c7, c5, 4   @ Flush Prefetch Buffer
 	fmxr fpexc, r2              @ Write Floating-point exception register