diff --git a/Inc/common_defines.h b/Inc/common_defines.h
index dbc2fa2..82b0a5e 100644
--- a/Inc/common_defines.h
+++ b/Inc/common_defines.h
@@ -11,7 +11,7 @@
 
 //#define DEBUG
 
-#define FIRMWARE_VERSION					0x1516			// v1.5.1b6
+#define FIRMWARE_VERSION					0x1517			// v1.5.1b7
 #define USED_PINS_NUM							30					// constant for BluePill and BlackPill boards
 #define MAX_AXIS_NUM							8						// max 8
 #define MAX_BUTTONS_NUM						128					// power of 2, max 128
diff --git a/Inc/main.h b/Inc/main.h
index 2e01955..933f17a 100644
--- a/Inc/main.h
+++ b/Inc/main.h
@@ -18,7 +18,7 @@
 
 static const dev_config_t init_config =
 {
-	.firmware_version = 0x1516,		// do not change
+	.firmware_version = 0x1517,		// do not change
 	
 	/* 
 		Name of device in devices dispatcher
diff --git a/MDK-ARM/FreeJoy.bin b/MDK-ARM/FreeJoy.bin
index 978baf1..126582c 100644
Binary files a/MDK-ARM/FreeJoy.bin and b/MDK-ARM/FreeJoy.bin differ
diff --git a/MDK-ARM/FreeJoy.uvoptx b/MDK-ARM/FreeJoy.uvoptx
index a58efa2..3a4dbf9 100644
--- a/MDK-ARM/FreeJoy.uvoptx
+++ b/MDK-ARM/FreeJoy.uvoptx
@@ -148,7 +148,24 @@
           <Name>UL2CM3(-S0 -C0 -P0 -FD20000000 -FC1000 -FN1 -FF0STM32F10x_128 -FS08000000 -FL020000 -FP0($$Device:STM32F103C8$Flash\STM32F10x_128.FLM))</Name>
         </SetRegEntry>
       </TargetDriverDllRegistry>
-      <Breakpoint/>
+      <Breakpoint>
+        <Bp>
+          <Number>0</Number>
+          <Type>0</Type>
+          <LineNumber>80</LineNumber>
+          <EnabledFlag>1</EnabledFlag>
+          <Address>134246376</Address>
+          <ByteObject>0</ByteObject>
+          <HtxType>0</HtxType>
+          <ManyObjects>0</ManyObjects>
+          <SizeOfObject>0</SizeOfObject>
+          <BreakByAccess>0</BreakByAccess>
+          <BreakIfRCount>1</BreakIfRCount>
+          <Filename>../Src/main.c</Filename>
+          <ExecCommand></ExecCommand>
+          <Expression>\\FreeJoy\../Src/main.c\80</Expression>
+        </Bp>
+      </Breakpoint>
       <WatchWindow1>
         <Ww>
           <count>0</count>
@@ -205,6 +222,11 @@
           <WinNumber>1</WinNumber>
           <ItemText>shift_registers,0x0A</ItemText>
         </Ww>
+        <Ww>
+          <count>11</count>
+          <WinNumber>1</WinNumber>
+          <ItemText>leds_state</ItemText>
+        </Ww>
       </WatchWindow1>
       <Tracepoint>
         <THDelay>0</THDelay>
@@ -248,6 +270,12 @@
       <pszMrulep></pszMrulep>
       <pSingCmdsp></pSingCmdsp>
       <pMultCmdsp></pMultCmdsp>
+      <SystemViewers>
+        <Entry>
+          <Name>System Viewer\GPIOB</Name>
+          <WinId>35905</WinId>
+        </Entry>
+      </SystemViewers>
       <DebugDescription>
         <Enable>1</Enable>
         <EnableFlashSeq>1</EnableFlashSeq>
@@ -594,6 +622,22 @@
           <ExecCommand></ExecCommand>
           <Expression></Expression>
         </Bp>
+        <Bp>
+          <Number>13</Number>
+          <Type>0</Type>
+          <LineNumber>80</LineNumber>
+          <EnabledFlag>1</EnabledFlag>
+          <Address>0</Address>
+          <ByteObject>0</ByteObject>
+          <HtxType>0</HtxType>
+          <ManyObjects>0</ManyObjects>
+          <SizeOfObject>0</SizeOfObject>
+          <BreakByAccess>0</BreakByAccess>
+          <BreakIfRCount>0</BreakIfRCount>
+          <Filename>../Src/main.c</Filename>
+          <ExecCommand></ExecCommand>
+          <Expression></Expression>
+        </Bp>
       </Breakpoint>
       <MemoryWindow1>
         <Mm>
diff --git a/Src/leds.c b/Src/leds.c
index 55c633b..93097f8 100644
--- a/Src/leds.c
+++ b/Src/leds.c
@@ -54,7 +54,14 @@ void LED_SetSingle(uint8_t * state_buf, dev_config_t * p_dev_config, uint8_t * p
 	{
 		if (p_dev_config->pins[i] == LED_SINGLE)
 		{
-			leds_state[(*pos)] ? (pin_config[i].port->ODR |= pin_config[i].pin) : (pin_config[i].port->ODR &= !pin_config[i].pin); 
+			if (leds_state[*pos])
+			{
+				pin_config[i].port->ODR |= pin_config[i].pin;
+			}
+			else
+			{
+				pin_config[i].port->ODR &= ~pin_config[i].pin; 
+			}
 			(*pos)++;
 		}
 	}
diff --git a/Src/stm32f10x_it.c b/Src/stm32f10x_it.c
index ddfe1fd..817923e 100644
--- a/Src/stm32f10x_it.c
+++ b/Src/stm32f10x_it.c
@@ -173,7 +173,7 @@ void SysTick_Handler(void)
 
 void TIM1_UP_IRQHandler(void)
 {
-	uint8_t btn_num = 0;
+	static uint8_t btn_num = 0;
 	uint8_t	physical_buttons_data[MAX_BUTTONS_NUM];
 	joy_report_t joy_report;