diff --git a/source/platform/stm32f1/buzzer.c b/source/platform/stm32f1/buzzer.c
index 4b361a9..7302fc5 100644
--- a/source/platform/stm32f1/buzzer.c
+++ b/source/platform/stm32f1/buzzer.c
@@ -6,9 +6,9 @@
 #include <macros.h>
 
 struct buzzer buzzers[] = {
-	{ TIM2, TIM_OC3 },
-	{ TIM2, TIM_OC4 },
+	{ TIM2, TIM_OC1 },
 };
+
 size_t nbuzzers = count_of(buzzers);
 
 void buzzer_init(struct buzzer *buzzer)
diff --git a/source/platform/stm32f1/gpio.c b/source/platform/stm32f1/gpio.c
index 9fac16b..c8bba8f 100644
--- a/source/platform/stm32f1/gpio.c
+++ b/source/platform/stm32f1/gpio.c
@@ -32,13 +32,13 @@ int gpio_init(void)
 	/* Set up GPIOs for timers. */
 	gpio_primary_remap(0, AFIO_MAPR_TIM2_REMAP_PARTIAL_REMAP1);
 	gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ,
-		GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_TIM2_PR1_CH3);
-	gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ,
-		GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_TIM2_PR1_CH4);
+		GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_TIM2_PR1_CH1_ETR);
 
 	/* Set up GPIO for LED. */
 	gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO0);
 	gpio_clear(GPIOB, GPIO0);
+	gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO10);
+	gpio_set(GPIOC, GPIO10);
 
 	return 0;
 }
diff --git a/source/platform/stm32f1/led.c b/source/platform/stm32f1/led.c
index 0214ea6..a867ba5 100644
--- a/source/platform/stm32f1/led.c
+++ b/source/platform/stm32f1/led.c
@@ -4,8 +4,9 @@
 #include <macros.h>
 
 struct led leds[] = {
-	{ GPIOB, GPIO0, 1 },
+	{ GPIOC, GPIO10, 1 },
 };
+
 size_t nleds = count_of(leds);
 
 void led_enable(struct led *led)
diff --git a/source/platform/stm32f1/rcc.c b/source/platform/stm32f1/rcc.c
index 9297e29..c099f2f 100644
--- a/source/platform/stm32f1/rcc.c
+++ b/source/platform/stm32f1/rcc.c
@@ -7,6 +7,7 @@ int rcc_init(void)
 	rcc_periph_clock_enable(RCC_AFIO);
 	rcc_periph_clock_enable(RCC_GPIOA);
 	rcc_periph_clock_enable(RCC_GPIOB);
+	rcc_periph_clock_enable(RCC_GPIOC);
 	rcc_periph_clock_enable(RCC_SPI1);
 	rcc_periph_clock_enable(RCC_USART1);
 	rcc_periph_clock_enable(RCC_USART2);