diff --git a/src/pulses_arm.cpp b/src/pulses_arm.cpp
index 41c4a2139..4994c4f10 100644
--- a/src/pulses_arm.cpp
+++ b/src/pulses_arm.cpp
@@ -288,7 +288,7 @@ void putPcmHead()
 
 void setupPulsesPXX()
 {
-  uint16_t chan, chan_low;
+  uint16_t chan=0, chan_low=0;
 
 #if defined(PCBSKY9X)
   Serial_byte = 0 ;
diff --git a/src/simpgmspace.h b/src/simpgmspace.h
index 4d3ea703a..f2d045012 100644
--- a/src/simpgmspace.h
+++ b/src/simpgmspace.h
@@ -362,7 +362,6 @@ inline void GPIO_Init(GPIO_TypeDef* GPIOx, GPIO_InitTypeDef* GPIO_InitStruct) {
 #define GPIO_ResetBits(GPIOx, pin) GPIOx->BSRRL &= ~pin
 #define GPIO_IsSet(GPIOx, pin) (GPIOx->BSRRL & pin)
 #define RCC_AHB1PeriphClockCmd(...)
-#define GPIO_ReadInputDataBit(...) true
 #endif
 
 #define configure_pins(...)
diff --git a/src/taranis/board_taranis.h b/src/taranis/board_taranis.h
index 5eeb4e406..e5d945ab6 100644
--- a/src/taranis/board_taranis.h
+++ b/src/taranis/board_taranis.h
@@ -165,7 +165,7 @@ void pwrOff();
 #define setBacklight(xx)
 #define __BACKLIGHT_ON    GPIO_SetBits(GPIOB, GPIO_Pin_BL)
 #define __BACKLIGHT_OFF   GPIO_ResetBits(GPIOB, GPIO_Pin_BL)
-#define IS_BACKLIGHT_ON() GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_BL)
+#define IS_BACKLIGHT_ON() GPIO_IsSet(GPIOB, GPIO_Pin_BL)
 
 // USB driver
 void usbInit(void);