add: add interrupt-based demo for F429

add: add doxygen description for USBD_SOF_OUT preprocessor variable
rmv: remove MCO clockout for F429 in cdc_startup.c (was added for debug purposes)
upd: update makefile for F429

Github issue #9

Makefile

@@ -48,6 +48,8 @@ help all:
 	@echo '  32l476rg-nucleo'
 	@echo '  stm32l476rg   CDC loopback demo for STM32L476xG based boards'
 	@echo '  stm32l052x8   CDC loopback demo for STM32L052x8 based boards'
+	@echo '  32f429zi-nucleo'
+	@echo '  stm32f429xi   CDC loopback demo for STM32F429xI based boards'
 	@echo '  doc           DOXYGEN documentation'
 	@echo '  module        static library module using following envars (defaults)'
 	@echo '                MODULE  module name (libusb.a)'

demo/cdc_loop.c

@@ -297,6 +297,9 @@ static void cdc_init_usbd(void) {
 #elif defined(STM32F103x6)
     #define USB_HANDLER     USB_LP_CAN1_RX0_IRQHandler
     #define USB_NVIC_IRQ    USB_LP_CAN1_RX0_IRQn
+#elif defined(STM32F429xx)
+    #define USB_HANDLER     OTG_FS_IRQHandler
+    #define USB_NVIC_IRQ    OTG_FS_IRQn
 #else
     #error Not supported
 #endif

demo/cdc_startup.c

@@ -109,11 +109,6 @@ static void cdc_init_rcc (void) {
     _BST(RCC->AHB1ENR, RCC_AHB1ENR_GPIOAEN);
     _BST(GPIOA->AFR[1], (0x0A << 12) | (0x0A << 16));
     _BMD(GPIOA->MODER, (0x03 << 22) | (0x03 << 24), (0x02 << 22) | (0x02 << 24));
-
-    _BST(RCC->AHB1ENR, RCC_AHB1ENR_GPIOCEN);
-    _BMD(GPIOC->MODER, (0x03 << 18), (0x02 << 18));
-    _BMD(RCC->CFGR, RCC_CFGR_MCO2, RCC_CFGR_MCO2PRE_2);
-
 #else
     #error Not supported
 #endif

inc/usbd_core.h

@@ -25,9 +25,10 @@
 /**\name Compile-time control macros
  * @{ */
 #define USBD_SOF_DISABLED   /**<\brief Disables SOF handling.*/
-#define USBD_VBUS_DETECT    /**<\brief Enables Vbus detection for V2 driver.*/
+#define USBD_VBUS_DETECT    /**<\brief Enables Vbus detection for L4/F4 driver.*/
 #define USBD_DP_PORT        /**<\brief DP pullup port for F103/F303 driver.*/
 #define USBD_DP_PIN         /**<\brief DP pullup pin for F103/F303 driver.*/
+#define USBD_SOF_OUT        /**<\brief Enables SOF output pin for F4 OTGFS. */
 /** @} */
 #endif