diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index a663f3ceb..551c7cb92 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -1,6 +1,6 @@
 name: Build
 
-on: [pull_request, push]
+on: [pull_request, push, repository_dispatch]
 
 jobs:
   unit-test:
diff --git a/examples/device/net_lwip_webserver/src/main.c b/examples/device/net_lwip_webserver/src/main.c
index c193aeb0f..fe904e8e8 100644
--- a/examples/device/net_lwip_webserver/src/main.c
+++ b/examples/device/net_lwip_webserver/src/main.c
@@ -53,7 +53,8 @@ static struct pbuf *received_frame;
 
 /* this is used by this code, ./class/net/net_driver.c, and usb_descriptors.c */
 /* ideally speaking, this should be generated from the hardware's unique ID (if available) */
-const uint8_t tud_network_mac_address[6] = {0x20,0x89,0x84,0x6A,0x96,0x00};
+/* it is suggested that the first two bytes are 0x02,0x02 to indicate a link-local address */
+const uint8_t tud_network_mac_address[6] = {0x02,0x02,0x84,0x6A,0x96,0x00};
 
 /* network parameters of this MCU */
 static const ip_addr_t ipaddr  = IPADDR4_INIT_BYTES(192, 168, 7, 1);
@@ -124,8 +125,11 @@ static void init_lwip(void)
   struct netif *netif = &netif_data;
 
   lwip_init();
+
+  /* the lwip virtual MAC address must be different from the host's; to ensure this, we toggle the LSbit */
   netif->hwaddr_len = sizeof(tud_network_mac_address);
   memcpy(netif->hwaddr, tud_network_mac_address, sizeof(tud_network_mac_address));
+  netif->hwaddr[5] ^= 0x01;
 
   netif = netif_add(netif, &ipaddr, &netmask, &gateway, NULL, netif_init_cb, ip_input);
   netif_set_default(netif);
diff --git a/examples/device/net_lwip_webserver/src/usb_descriptors.c b/examples/device/net_lwip_webserver/src/usb_descriptors.c
index c7a8cc767..a4eba205f 100644
--- a/examples/device/net_lwip_webserver/src/usb_descriptors.c
+++ b/examples/device/net_lwip_webserver/src/usb_descriptors.c
@@ -112,7 +112,7 @@ uint8_t const desc_configuration[] =
 
 #if CFG_TUD_NET == OPT_NET_ECM
   // Interface number, description string index, MAC address string index, EP notification address and size, EP data address (out, in), and size, max segment size.
-  TUD_CDC_ECM_DESCRIPTOR(ITF_NUM_CDC, STRID_INTERFACE, STRID_MAC, 0x81, 8, EPNUM_CDC, 0x80 | EPNUM_CDC, CFG_TUD_NET_ENDPOINT_SIZE, CFG_TUD_NET_MTU),
+  TUD_CDC_ECM_DESCRIPTOR(ITF_NUM_CDC, STRID_INTERFACE, STRID_MAC, 0x81, 64, EPNUM_CDC, 0x80 | EPNUM_CDC, CFG_TUD_NET_ENDPOINT_SIZE, CFG_TUD_NET_MTU),
 #elif CFG_TUD_NET == OPT_NET_RNDIS
   // Interface number, string index, EP notification address and size, EP data address (out, in) and size.
   TUD_RNDIS_DESCRIPTOR(ITF_NUM_CDC, STRID_INTERFACE, 0x81, 8, EPNUM_CDC, 0x80 | EPNUM_CDC, CFG_TUD_NET_ENDPOINT_SIZE),
diff --git a/hw/bsp/stm32f070rbnucleo/stm32f070rbnucleo.c b/hw/bsp/stm32f070rbnucleo/stm32f070rbnucleo.c
index 56b3024e3..3cb91f75a 100644
--- a/hw/bsp/stm32f070rbnucleo/stm32f070rbnucleo.c
+++ b/hw/bsp/stm32f070rbnucleo/stm32f070rbnucleo.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f0xx.h"
-#include "stm32f0xx_hal_conf.h"
+#include "stm32f0xx_hal.h"
 
 #define LED_PORT              GPIOA
 #define LED_PIN               GPIO_PIN_5
@@ -57,10 +56,7 @@ static void all_rcc_clk_enable(void)
 
 void board_init(void)
 {
-  #if CFG_TUSB_OS  == OPT_OS_NONE
-  // 1ms tick timer
-  SysTick_Config(SystemCoreClock / 1000);
-  #endif
+
 
   /* Configure the system clock to 48 MHz */
   RCC_ClkInitTypeDef RCC_ClkInitStruct;
@@ -90,10 +86,13 @@ void board_init(void)
   (void)HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) ;
   
   // Notify runtime of frequency change.
-  SystemCoreClockUpdate();
-
   all_rcc_clk_enable();
 
+  #if CFG_TUSB_OS  == OPT_OS_NONE
+  // 1ms tick timer
+  SysTick_Config(SystemCoreClock / 1000);
+  #endif
+
   // LED
   GPIO_InitTypeDef  GPIO_InitStruct;
   GPIO_InitStruct.Pin = LED_PIN;
diff --git a/hw/bsp/stm32f072disco/stm32f072disco.c b/hw/bsp/stm32f072disco/stm32f072disco.c
index e26c5628a..faf339849 100644
--- a/hw/bsp/stm32f072disco/stm32f072disco.c
+++ b/hw/bsp/stm32f072disco/stm32f072disco.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f0xx.h"
-#include "stm32f0xx_hal_conf.h"
+#include "stm32f0xx_hal.h"
 
 #define LED_PORT              GPIOC
 #define LED_PIN               GPIO_PIN_6
@@ -95,16 +94,14 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
   #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
   #endif
 
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  
-  all_rcc_clk_enable();
-
   // LED
   GPIO_InitTypeDef  GPIO_InitStruct;
   GPIO_InitStruct.Pin = LED_PIN;
diff --git a/hw/bsp/stm32f103bluepill/stm32f103bluepill.c b/hw/bsp/stm32f103bluepill/stm32f103bluepill.c
index 24c898c84..e68bdd1bf 100644
--- a/hw/bsp/stm32f103bluepill/stm32f103bluepill.c
+++ b/hw/bsp/stm32f103bluepill/stm32f103bluepill.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f1xx.h"
-#include "stm32f1xx_hal_conf.h"
+#include "stm32f1xx_hal.h"
 
 #define LED_PORT              GPIOC
 #define LED_PIN               GPIO_PIN_13
@@ -85,16 +84,14 @@ void SystemClock_Config(void)
 
 void board_init(void)
 {
+
+  SystemClock_Config();
+  
   #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
   #endif
-
-  SystemClock_Config();
   
-  // Notify runtime of frequency change.
-  SystemCoreClockUpdate();
-
   // LED
   __HAL_RCC_GPIOC_CLK_ENABLE();
   GPIO_InitTypeDef  GPIO_InitStruct;
diff --git a/hw/bsp/stm32f207nucleo/stm32f207nucleo.c b/hw/bsp/stm32f207nucleo/stm32f207nucleo.c
index 178c0e8c6..29e69cc88 100644
--- a/hw/bsp/stm32f207nucleo/stm32f207nucleo.c
+++ b/hw/bsp/stm32f207nucleo/stm32f207nucleo.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f2xx.h"
-#include "stm32f2xx_hal_conf.h"
+#include "stm32f2xx_hal.h"
 
 #define LED_PORT              GPIOB
 #define LED_PIN               GPIO_PIN_14
@@ -93,13 +92,13 @@ void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  
   #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
   #endif
 
-  SystemClock_Config();
-  SystemCoreClockUpdate();
 
   all_rcc_clk_enable();
 
diff --git a/hw/bsp/stm32f303disco/stm32f303disco.c b/hw/bsp/stm32f303disco/stm32f303disco.c
index d6d97a531..44a342e04 100644
--- a/hw/bsp/stm32f303disco/stm32f303disco.c
+++ b/hw/bsp/stm32f303disco/stm32f303disco.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f3xx.h"
-#include "stm32f3xx_hal_conf.h"
+#include "stm32f3xx_hal.h"
 
 #define LED_PORT              GPIOE
 #define LED_PIN               GPIO_PIN_9
@@ -89,16 +88,13 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+
   #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
   #endif
 
-  SystemClock_Config();
-
-  // Notify runtime of frequency change.
-  SystemCoreClockUpdate();
-
   // LED
   __HAL_RCC_GPIOE_CLK_ENABLE();
   GPIO_InitTypeDef  GPIO_InitStruct;
diff --git a/hw/bsp/stm32f401blackpill/stm32f401blackpill.c b/hw/bsp/stm32f401blackpill/stm32f401blackpill.c
index 1fc5bb566..5d3375f01 100644
--- a/hw/bsp/stm32f401blackpill/stm32f401blackpill.c
+++ b/hw/bsp/stm32f401blackpill/stm32f401blackpill.c
@@ -100,6 +100,9 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
 #if CFG_TUSB_OS == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
@@ -107,11 +110,7 @@ void board_init(void)
   // If freeRTOS is used, IRQ priority is limit by max syscall ( smaller is higher )
   //NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
-
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  all_rcc_clk_enable();
-
+  
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
diff --git a/hw/bsp/stm32f407disco/board.mk b/hw/bsp/stm32f407disco/board.mk
index 9800b9cb2..92c349d09 100644
--- a/hw/bsp/stm32f407disco/board.mk
+++ b/hw/bsp/stm32f407disco/board.mk
@@ -19,6 +19,7 @@ SRC_C += \
 	$(ST_CMSIS)/Source/Templates/system_stm32f4xx.c \
 	$(ST_HAL_DRIVER)/Src/stm32f4xx_hal.c \
 	$(ST_HAL_DRIVER)/Src/stm32f4xx_hal_cortex.c \
+	$(ST_HAL_DRIVER)/Src/stm32f4xx_hal_uart.c \
 	$(ST_HAL_DRIVER)/Src/stm32f4xx_hal_rcc.c \
 	$(ST_HAL_DRIVER)/Src/stm32f4xx_hal_gpio.c
 
diff --git a/hw/bsp/stm32f407disco/stm32f407disco.c b/hw/bsp/stm32f407disco/stm32f407disco.c
index 88d50efd5..d1e927f2a 100644
--- a/hw/bsp/stm32f407disco/stm32f407disco.c
+++ b/hw/bsp/stm32f407disco/stm32f407disco.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f4xx.h"
-#include "stm32f4xx_hal_conf.h"
+#include "stm32f4xx_hal.h"
 
 #define LED_PORT              GPIOD
 #define LED_PIN               GPIO_PIN_14
@@ -38,11 +37,22 @@
 #define BUTTON_STATE_ACTIVE   1
 
 
+// Enable PA2 as the debug log UART
+// It is not routed to the ST/Link on the Discovery board.
+#define UARTx                 USART2
+#define UART_GPIO_PORT        GPIOA
+#define UART_GPIO_AF          GPIO_AF7_USART2
+#define UART_TX_PIN           GPIO_PIN_2
+#define UART_RX_PIN           GPIO_PIN_3
+
+UART_HandleTypeDef UartHandle;
+
 // enable all LED, Button, Uart, USB clock
 static void all_rcc_clk_enable(void)
 {
   __HAL_RCC_GPIOA_CLK_ENABLE();  // USB D+, D-, Button
   __HAL_RCC_GPIOD_CLK_ENABLE();  // LED
+  __HAL_RCC_USART2_CLK_ENABLE(); // Uart module
 }
 
 /**
@@ -101,6 +111,9 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
 #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
@@ -109,10 +122,6 @@ void board_init(void)
   //NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
 
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  all_rcc_clk_enable();
-
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
@@ -155,6 +164,25 @@ void board_init(void)
   GPIO_InitStruct.Alternate = GPIO_AF10_OTG_FS;
   HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
+  GPIO_InitStruct.Pin       = UART_TX_PIN | UART_RX_PIN;
+  GPIO_InitStruct.Mode      = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull      = GPIO_PULLUP;
+  GPIO_InitStruct.Speed     = GPIO_SPEED_FREQ_HIGH;
+  GPIO_InitStruct.Alternate = UART_GPIO_AF;
+  HAL_GPIO_Init(UART_GPIO_PORT, &GPIO_InitStruct);
+
+  UartHandle = (UART_HandleTypeDef){
+    .Instance        = UARTx,
+    .Init.BaudRate   = CFG_BOARD_UART_BAUDRATE,
+    .Init.WordLength = UART_WORDLENGTH_8B,
+    .Init.StopBits   = UART_STOPBITS_1,
+    .Init.Parity     = UART_PARITY_NONE,
+    .Init.HwFlowCtl  = UART_HWCONTROL_NONE,
+    .Init.Mode       = UART_MODE_TX_RX,
+    .Init.OverSampling = UART_OVERSAMPLING_16
+  };
+  HAL_UART_Init(&UartHandle);
+
   // Enable USB OTG clock
   __HAL_RCC_USB_OTG_FS_CLK_ENABLE();
 
@@ -185,8 +213,8 @@ int board_uart_read(uint8_t* buf, int len)
 
 int board_uart_write(void const * buf, int len)
 {
-  (void) buf; (void) len;
-  return 0;
+  HAL_UART_Transmit(&UartHandle, (uint8_t*) buf, len, 0xffff);
+  return len;
 }
 
 #if CFG_TUSB_OS  == OPT_OS_NONE
diff --git a/hw/bsp/stm32f407disco/stm32f4xx_hal_conf.h b/hw/bsp/stm32f407disco/stm32f4xx_hal_conf.h
index d9a690041..ca7723764 100644
--- a/hw/bsp/stm32f407disco/stm32f4xx_hal_conf.h
+++ b/hw/bsp/stm32f407disco/stm32f4xx_hal_conf.h
@@ -79,7 +79,7 @@
 /* #define HAL_SD_MODULE_ENABLED         */
 // #define HAL_SPI_MODULE_ENABLED
 /* #define HAL_TIM_MODULE_ENABLED       */
-/* #define HAL_UART_MODULE_ENABLED      */
+#define HAL_UART_MODULE_ENABLED
 /* #define HAL_USART_MODULE_ENABLED     */ 
 /* #define HAL_IRDA_MODULE_ENABLED      */
 /* #define HAL_SMARTCARD_MODULE_ENABLED */
diff --git a/hw/bsp/stm32f411blackpill/stm32f411blackpill.c b/hw/bsp/stm32f411blackpill/stm32f411blackpill.c
index 1fc5bb566..3dd74fc71 100644
--- a/hw/bsp/stm32f411blackpill/stm32f411blackpill.c
+++ b/hw/bsp/stm32f411blackpill/stm32f411blackpill.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f4xx.h"
-#include "stm32f4xx_hal_conf.h"
+#include "stm32f4xx_hal.h"
 
 #define LED_PORT              GPIOC
 #define LED_PIN               GPIO_PIN_13
@@ -100,6 +99,9 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
 #if CFG_TUSB_OS == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
@@ -108,10 +110,6 @@ void board_init(void)
   //NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
 
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  all_rcc_clk_enable();
-
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
diff --git a/hw/bsp/stm32f411disco/stm32f411disco.c b/hw/bsp/stm32f411disco/stm32f411disco.c
index 04e211f21..acbcc405e 100644
--- a/hw/bsp/stm32f411disco/stm32f411disco.c
+++ b/hw/bsp/stm32f411disco/stm32f411disco.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32f4xx.h"
-#include "stm32f4xx_hal_conf.h"
+#include "stm32f4xx_hal.h"
 
 #define LED_PORT              GPIOD
 #define LED_PIN               GPIO_PIN_13
@@ -100,6 +99,9 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
 #if CFG_TUSB_OS == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
@@ -108,10 +110,6 @@ void board_init(void)
   //NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
 
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  all_rcc_clk_enable();
-
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
diff --git a/hw/bsp/stm32f412disco/stm32f412disco.c b/hw/bsp/stm32f412disco/stm32f412disco.c
index 97291d8b3..4d60112f6 100644
--- a/hw/bsp/stm32f412disco/stm32f412disco.c
+++ b/hw/bsp/stm32f412disco/stm32f412disco.c
@@ -122,7 +122,6 @@ static void SystemClock_Config(void)
 void board_init(void)
 {
   SystemClock_Config();
-  SystemCoreClockUpdate();
   all_rcc_clk_enable();
 
 #if CFG_TUSB_OS == OPT_OS_NONE
diff --git a/hw/bsp/stm32f767nucleo/stm32f767nucleo.c b/hw/bsp/stm32f767nucleo/stm32f767nucleo.c
index 228fd6e57..7a24bfa71 100644
--- a/hw/bsp/stm32f767nucleo/stm32f767nucleo.c
+++ b/hw/bsp/stm32f767nucleo/stm32f767nucleo.c
@@ -27,8 +27,7 @@
 
 #include "../board.h"
 
-#include "stm32f7xx.h"
-#include "stm32f7xx_hal_conf.h"
+#include "stm32f7xx_hal.h"
 
 #define LED_PORT              GPIOB
 #define LED_PIN               GPIO_PIN_14
@@ -121,16 +120,16 @@ void SystemClock_Config(void)
 
 void board_init(void)
 {
-  #if CFG_TUSB_OS  == OPT_OS_NONE
-    // 1ms tick timer
-    SysTick_Config(SystemCoreClock / 1000);
-  #endif
+
 
   SystemClock_Config();
-  SystemCoreClockUpdate();
-
   all_rcc_clk_enable();
 
+#if CFG_TUSB_OS  == OPT_OS_NONE
+  // 1ms tick timer
+  SysTick_Config(SystemCoreClock / 1000);
+#endif
+
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
diff --git a/hw/bsp/stm32h743nucleo/stm32h743nucleo.c b/hw/bsp/stm32h743nucleo/stm32h743nucleo.c
index 022827f5e..593b6e50e 100644
--- a/hw/bsp/stm32h743nucleo/stm32h743nucleo.c
+++ b/hw/bsp/stm32h743nucleo/stm32h743nucleo.c
@@ -27,8 +27,7 @@
 
 #include "../board.h"
 
-#include "stm32h7xx.h"
-#include "stm32h7xx_hal_conf.h"
+#include "stm32h7xx_hal.h"
 
 #define LED_PORT              GPIOB
 #define LED_PIN               GPIO_PIN_0
@@ -98,6 +97,7 @@ static void SystemClock_Config(void)
   RCC_OscInitStruct.PLL.PLLN = 336;
   RCC_OscInitStruct.PLL.PLLP = 2;
   RCC_OscInitStruct.PLL.PLLQ = 7;
+  RCC_OscInitStruct.PLL.PLLR = 2; /* Unused */
   RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_0;
   RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOMEDIUM;
   RCC_OscInitStruct.PLL.PLLFRACN = 0;
@@ -134,15 +134,14 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
   #if CFG_TUSB_OS  == OPT_OS_NONE
     // 1ms tick timer
     SysTick_Config(SystemCoreClock / 1000);
   #endif
-
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  all_rcc_clk_enable();
-
+  
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
diff --git a/hw/bsp/stm32l0538disco/stm32l0538disco.c b/hw/bsp/stm32l0538disco/stm32l0538disco.c
index 6b0222ea0..2d9b49951 100644
--- a/hw/bsp/stm32l0538disco/stm32l0538disco.c
+++ b/hw/bsp/stm32l0538disco/stm32l0538disco.c
@@ -26,8 +26,7 @@
 
 #include "../board.h"
 
-#include "stm32l0xx.h"
-#include "stm32l0xx_hal_conf.h"
+#include "stm32l0xx_hal.h"
 
 #define LED_PORT              GPIOA
 #define LED_PIN               GPIO_PIN_5
@@ -101,6 +100,8 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+
 #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
@@ -109,11 +110,6 @@ void board_init(void)
   //NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
 
-  SystemClock_Config();
-
-  // Notify runtime of frequency change.
-  SystemCoreClockUpdate();
-
   GPIO_InitTypeDef  GPIO_InitStruct;
 
   // LED
diff --git a/hw/bsp/stm32l476disco/stm32l476disco.c b/hw/bsp/stm32l476disco/stm32l476disco.c
index ac4ef365c..db755c18d 100644
--- a/hw/bsp/stm32l476disco/stm32l476disco.c
+++ b/hw/bsp/stm32l476disco/stm32l476disco.c
@@ -26,8 +26,6 @@
 
 #include "../board.h"
 
-#include "stm32l4xx.h"
-#include "stm32l4xx_hal_conf.h"
 #include "stm32l4xx_hal.h"
 
 #define LED_PORT              GPIOB
@@ -118,6 +116,9 @@ static void SystemClock_Config(void)
 
 void board_init(void)
 {
+  SystemClock_Config();
+  all_rcc_clk_enable();
+
 #if CFG_TUSB_OS  == OPT_OS_NONE
   // 1ms tick timer
   SysTick_Config(SystemCoreClock / 1000);
@@ -126,10 +127,6 @@ void board_init(void)
   //NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
 
-  SystemClock_Config();
-  SystemCoreClockUpdate();
-  all_rcc_clk_enable();
-
   /* Enable Power Clock*/
   __HAL_RCC_PWR_CLK_ENABLE();
 
diff --git a/src/class/net/net_device.c b/src/class/net/net_device.c
index 7bb11d57c..68520625a 100644
--- a/src/class/net/net_device.c
+++ b/src/class/net/net_device.c
@@ -63,7 +63,15 @@ typedef struct
 CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN static uint8_t received[CFG_TUD_NET_PACKET_PREFIX_LEN + CFG_TUD_NET_MTU + CFG_TUD_NET_PACKET_PREFIX_LEN];
 CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN static uint8_t transmitted[CFG_TUD_NET_PACKET_PREFIX_LEN + CFG_TUD_NET_MTU + CFG_TUD_NET_PACKET_PREFIX_LEN];
 
-#if CFG_TUD_NET == OPT_NET_RNDIS
+#if CFG_TUD_NET == OPT_NET_ECM
+  CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN static tusb_control_request_t notify =
+  {
+    .bmRequestType = 0x21,
+    .bRequest = 0 /* NETWORK_CONNECTION */,
+    .wValue = 1 /* Connected */,
+    .wLength = 0,
+  };
+#elif CFG_TUD_NET == OPT_NET_RNDIS
   CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN static uint8_t rndis_buf[120];
 #endif
 
@@ -197,7 +205,15 @@ bool netd_control_request(uint8_t rhport, tusb_control_request_t const * request
 
   TU_VERIFY (_netd_itf.itf_num == request->wIndex);
 
-#if CFG_TUD_NET == OPT_NET_RNDIS
+#if CFG_TUD_NET == OPT_NET_ECM
+  /* the only required CDC-ECM Management Element Request is SetEthernetPacketFilter */
+  if (0x43 /* SET_ETHERNET_PACKET_FILTER */ == request->bRequest)
+  {
+    tud_control_xfer(rhport, request, NULL, 0);
+    notify.wIndex = request->wIndex;
+    usbd_edpt_xfer(TUD_OPT_RHPORT, _netd_itf.ep_notif, (uint8_t *)&notify, sizeof(notify));
+  }
+#elif CFG_TUD_NET == OPT_NET_RNDIS
   if (request->bmRequestType_bit.direction == TUSB_DIR_IN)
   {
     rndis_generic_msg_t *rndis_msg = (rndis_generic_msg_t *)rndis_buf;
diff --git a/src/device/usbd_control.c b/src/device/usbd_control.c
index 4fd40c440..c61606f18 100644
--- a/src/device/usbd_control.c
+++ b/src/device/usbd_control.c
@@ -101,22 +101,29 @@ static bool _data_stage_xact(uint8_t rhport)
   return dcd_edpt_xfer(rhport, ep_addr, xact_len ? _usbd_ctrl_buf : NULL, xact_len);
 }
 
+// Transmit data to/from the control endpoint.
+// 
+// If the request's wLength is zero, a status packet is sent instead.
 bool tud_control_xfer(uint8_t rhport, tusb_control_request_t const * request, void* buffer, uint16_t len)
 {
   _ctrl_xfer.request       = (*request);
   _ctrl_xfer.buffer        = (uint8_t*) buffer;
-  _ctrl_xfer.total_xferred = 0;
+  _ctrl_xfer.total_xferred = 0U;
   _ctrl_xfer.data_len      = tu_min16(len, request->wLength);
-
-  if ( _ctrl_xfer.data_len )
+  
+  if (request->wLength > 0U)
   {
-    TU_ASSERT(buffer);
+    if(_ctrl_xfer.data_len > 0U)
+    {
+      TU_ASSERT(buffer);
+    }
 
     TU_LOG2("  XFER Endpoint: 0x%02X, Bytes: %d\r\n", request->bmRequestType_bit.direction ? EDPT_CTRL_IN : EDPT_CTRL_OUT, _ctrl_xfer.data_len);
 
     // Data stage
     TU_ASSERT( _data_stage_xact(rhport) );
-  }else
+  }
+  else
   {
     // Status stage
     TU_ASSERT( _status_stage_xact(rhport, request) );