diff --git a/demos/STM32/RT-STM32G031K8-NUCLEO32/cfg/mcuconf.h b/demos/STM32/RT-STM32G031K8-NUCLEO32/cfg/mcuconf.h
index 05c14bb49..188c37300 100644
--- a/demos/STM32/RT-STM32G031K8-NUCLEO32/cfg/mcuconf.h
+++ b/demos/STM32/RT-STM32G031K8-NUCLEO32/cfg/mcuconf.h
@@ -75,9 +75,9 @@
 /*
  * Peripherals clocks and sources.
  */
-#define STM32_USART1SEL                     STM32_USART1SEL_SYSCLK
-#define STM32_USART2SEL                     STM32_USART2SEL_SYSCLK
-#define STM32_LPUART1SEL                    STM32_LPUART1SEL_SYSCLK
+#define STM32_USART1SEL                     STM32_USART1SEL_PCLK
+#define STM32_USART2SEL                     STM32_USART2SEL_PCLK
+#define STM32_LPUART1SEL                    STM32_LPUART1SEL_PCLK
 #define STM32_I2C1SEL                       STM32_I2C1SEL_PCLK
 #define STM32_I2S1SEL                       STM32_I2S1SEL_SYSCLK
 #define STM32_LPTIM1SEL                     STM32_LPTIM1SEL_PCLK
diff --git a/os/hal/ports/STM32/STM32G0xx/stm32_isr.c b/os/hal/ports/STM32/STM32G0xx/stm32_isr.c
index 7c98d2234..f4eca8984 100644
--- a/os/hal/ports/STM32/STM32G0xx/stm32_isr.c
+++ b/os/hal/ports/STM32/STM32G0xx/stm32_isr.c
@@ -83,10 +83,12 @@
 
 #include "stm32_tim1.inc"
 #include "stm32_tim2.inc"
-#if STM32_HAS_TIM4
+#if STM32_HAS_TIM3 && STM32_HAS_TIM4
 #include "stm32_tim3_4.inc"
-#else
+#elif STM32_HAS_TIM3
 #include "stm32_tim3.inc"
+#else
+#error "unknown TIMs combination"
 #endif
 #include "stm32_tim6.inc"
 #include "stm32_tim7.inc"
@@ -113,9 +115,9 @@ void irqInit(void) {
 
   tim1_irq_init();
   tim2_irq_init();
-#if STM32_HAS_TIM4
+#if STM32_HAS_TIM3 && STM32_HAS_TIM4
   tim3_tim4_irq_init();
-#else
+#elif STM32_HAS_TIM3
   tim3_irq_init();
 #endif
   tim6_irq_init();
@@ -154,9 +156,9 @@ void irqDeinit(void) {
 
   tim1_irq_deinit();
   tim2_irq_deinit();
-#if STM32_HAS_TIM4
+#if STM32_HAS_TIM3 && STM32_HAS_TIM4
   tim3_tim4_irq_deinit();
-#else
+#elif STM32_HAS_TIM3
   tim3_irq_deinit();
 #endif
   tim6_irq_deinit();
diff --git a/tools/ftl/processors/conf/mcuconf_stm32g031xx/mcuconf.h.ftl b/tools/ftl/processors/conf/mcuconf_stm32g031xx/mcuconf.h.ftl
index 400746fb6..e0652b059 100644
--- a/tools/ftl/processors/conf/mcuconf_stm32g031xx/mcuconf.h.ftl
+++ b/tools/ftl/processors/conf/mcuconf_stm32g031xx/mcuconf.h.ftl
@@ -86,9 +86,9 @@
 /*
  * Peripherals clocks and sources.
  */
-#define STM32_USART1SEL                     ${doc.STM32_USART1SEL!"STM32_USART1SEL_SYSCLK"}
-#define STM32_USART2SEL                     ${doc.STM32_USART2SEL!"STM32_USART2SEL_SYSCLK"}
-#define STM32_LPUART1SEL                    ${doc.STM32_LPUART1SEL!"STM32_LPUART1SEL_SYSCLK"}
+#define STM32_USART1SEL                     ${doc.STM32_USART1SEL!"STM32_USART1SEL_PCLK"}
+#define STM32_USART2SEL                     ${doc.STM32_USART2SEL!"STM32_USART2SEL_PCLK"}
+#define STM32_LPUART1SEL                    ${doc.STM32_LPUART1SEL!"STM32_LPUART1SEL_PCLK"}
 #define STM32_I2C1SEL                       ${doc.STM32_I2C1SEL!"STM32_I2C1SEL_PCLK"}
 #define STM32_I2S1SEL                       ${doc.STM32_I2S1SEL!"STM32_I2S1SEL_SYSCLK"}
 #define STM32_LPTIM1SEL                     ${doc.STM32_LPTIM1SEL!"STM32_LPTIM1SEL_PCLK"}