diff --git a/examples/stm32/f0/stm32f0-discovery/systick_blink/systick_blink.c b/examples/stm32/f0/stm32f0-discovery/systick_blink/systick_blink.c
index 462dd83..89d71ab 100644
--- a/examples/stm32/f0/stm32f0-discovery/systick_blink/systick_blink.c
+++ b/examples/stm32/f0/stm32f0-discovery/systick_blink/systick_blink.c
@@ -37,7 +37,7 @@ static void systick_setup(int freq)
 	/* clear counter so it starts right away */
 	STK_CVR = 0;
 
-	systick_set_reload(rcc_core_frequency / freq);
+	systick_set_reload(rcc_ahb_frequency / freq);
 	systick_counter_enable();
 	systick_interrupt_enable();
 }
diff --git a/libopencm3 b/libopencm3
index 99f83ee..3974e5f 160000
--- a/libopencm3
+++ b/libopencm3
@@ -1 +1 @@
-Subproject commit 99f83eedcd1fe02cbebbe55ced496313815323d2
+Subproject commit 3974e5f48d35351bd31472b089a6ea0d42a633ee