Update systick reload value
The systick timer is driven by the AHB bus divided by 4, set the correct
reload value to generate a timer irq every ms.
@@ -39,7 +39,9 @@ void USBFS_IRQHandler(void) { tud_int_handler(0); }
#define USB_NO_VBUS_PIN
-#define TIMER_TICKS (SystemCoreClock / 1000)
+// According to GD32VF103 user manual clock tree:
+// Systick clock = AHB clock / 4.
+#define TIMER_TICKS ((SystemCoreClock / 4) / 1000)
#define BUTTON_PORT GPIOA
#define BUTTON_PIN GPIO_PIN_0
