arduino · pennam · Aug 5, 2025 · Aug 8, 2025 · Aug 8, 2025 · Apr 3, 2025
diff --git a/boards.txt b/boards.txt
@@ -463,7 +463,7 @@ portentac33.upload.native_usb=true
 portentac33.upload.maximum_size=1966080
 portentac33.upload.maximum_data_size=523624
 portentac33.upload.address=0x100000
-portentac33.upload.dfuse=-Q
+portentac33.upload.dfuse=-Q -w
 
 portentac33.bootloader.tool=dfu-util
 portentac33.bootloader.tool.default=dfu-util

diff --git a/cores/arduino/SerialUSB.h b/cores/arduino/SerialUSB.h
@@ -8,6 +8,11 @@
 
 #include <zephyrSerial.h>
 
+#if defined(CONFIG_USB_DEVICE_STACK_NEXT)
+#include <zephyr/usb/usbd.h>
+extern "C" struct usbd_context *usbd_init_device(usbd_msg_cb_t msg_cb);
+#endif
+
 namespace arduino {
 
 class SerialUSB_ : public ZephyrSerial {
@@ -25,12 +30,18 @@
 protected:
 	uint32_t dtr = 0;
 	uint32_t baudrate;
-	void _baudChangeHandler();
 	static void _baudChangeDispatch(struct k_timer *timer);
+	static void _baudChangeHandler(const struct device *dev, uint32_t rate);
 
 private:
-	struct k_timer baud_timer;
 	bool started = false;
+
+#if defined(CONFIG_USB_DEVICE_STACK_NEXT)
+	struct usbd_context *_usbd;
+	int enable_usb_device_next();
+	static void usbd_next_cb(struct usbd_context *const ctx, const struct usbd_msg *msg);
+	static int usb_disable();
+#endif
 };
 }  // namespace arduino
 

diff --git a/cores/arduino/USB.cpp b/cores/arduino/USB.cpp
@@ -24,62 +24,47 @@ void __attribute__((weak)) _on_1200_bps() {
     NVIC_SystemReset();
 }
 
-void arduino::SerialUSB_::_baudChangeHandler()
-{
-    uart_line_ctrl_get(uart, UART_LINE_CTRL_BAUD_RATE, &baudrate);
-    if (baudrate == 1200) {
-        usb_disable();
-        _on_1200_bps();
-    }
-}
-
-static void _baudChangeHandler(const struct device *dev, uint32_t rate)
+void arduino::SerialUSB_::_baudChangeHandler(const struct device *dev, uint32_t rate)
 {
     (void)dev; // unused
     if (rate == 1200) {
+        k_sleep(K_MSEC(100));
         usb_disable();
+        k_sleep(K_MSEC(10));
         _on_1200_bps();
     }
 }
 
 #if defined(CONFIG_USB_DEVICE_STACK_NEXT)
 
-extern "C" {
-    #include <zephyr/usb/usbd.h>
-    struct usbd_context *usbd_init_device(usbd_msg_cb_t msg_cb);
+int arduino::SerialUSB_::usb_disable() {
+    return usbd_disable(Serial._usbd);
 }
 
-struct usbd_context *_usbd;
-
-int usb_disable() {
-    return usbd_disable(_usbd);
-}
-
-static void usbd_next_cb(struct usbd_context *const ctx, const struct usbd_msg *msg)
+void arduino::SerialUSB_::usbd_next_cb(struct usbd_context *const ctx, const struct usbd_msg *msg)
 {
-	if (usbd_can_detect_vbus(ctx)) {
-		if (msg->type == USBD_MSG_VBUS_READY) {
-			usbd_enable(ctx);
-		}
-
-		if (msg->type == USBD_MSG_VBUS_REMOVED) {
-			usbd_disable(ctx);
-		}
-	}
+    if (usbd_can_detect_vbus(ctx)) {
+        if (msg->type == USBD_MSG_VBUS_READY) {
+            usbd_enable(ctx);
+        }
+
+        if (msg->type == USBD_MSG_VBUS_REMOVED) {
+            usbd_disable(ctx);
+        }
+    }
 
-	if (msg->type == USBD_MSG_CDC_ACM_LINE_CODING) {
+    if (msg->type == USBD_MSG_CDC_ACM_LINE_CODING) {
         uint32_t baudrate;
-		uart_line_ctrl_get(ctx->dev, UART_LINE_CTRL_BAUD_RATE, &baudrate);
-        _baudChangeHandler(nullptr, baudrate);
-	}
+        uart_line_ctrl_get(Serial.uart, UART_LINE_CTRL_BAUD_RATE, &baudrate);
+        Serial._baudChangeHandler(nullptr, baudrate);
+    }
 }
 
-static int enable_usb_device_next(void)
+int arduino::SerialUSB_::enable_usb_device_next(void)
 {
 	int err;
 
-	//_usbd = usbd_init_device(usbd_next_cb);
-	_usbd = usbd_init_device(nullptr);
+	_usbd = usbd_init_device(arduino::SerialUSB_::usbd_next_cb);
 	if (_usbd == NULL) {
 		return -ENODEV;
 	}
@@ -94,22 +79,14 @@ static int enable_usb_device_next(void)
 }
 #endif /* defined(CONFIG_USB_DEVICE_STACK_NEXT) */
 
-void arduino::SerialUSB_::_baudChangeDispatch(struct k_timer *timer) {
-    arduino::SerialUSB_* dev = (arduino::SerialUSB_*)k_timer_user_data_get(timer);
-    dev->_baudChangeHandler();
-}
-
-
 void arduino::SerialUSB_::begin(unsigned long baudrate, uint16_t config) {
     if (!started) {
         #ifndef CONFIG_USB_DEVICE_STACK_NEXT
         usb_enable(NULL);
         #ifndef CONFIG_CDC_ACM_DTE_RATE_CALLBACK_SUPPORT
-        k_timer_init(&baud_timer, SerialUSB_::_baudChangeDispatch, NULL);
-        k_timer_user_data_set(&baud_timer, this);
-        k_timer_start(&baud_timer, K_MSEC(100), K_MSEC(100));
+        #warning "Can't read CDC baud change, please enable CONFIG_CDC_ACM_DTE_RATE_CALLBACK_SUPPORT"
         #else
-        cdc_acm_dte_rate_callback_set(usb_dev, ::_baudChangeHandler);
+        cdc_acm_dte_rate_callback_set(usb_dev, SerialUSB_::_baudChangeHandler);
         #endif
         #else
         enable_usb_device_next();

diff --git a/cores/arduino/main.cpp b/cores/arduino/main.cpp
@@ -23,7 +23,7 @@ void __attribute__((weak))initVariant(void) {
 
 
 int main(void) {
-#if (DT_NODE_HAS_PROP(DT_PATH(zephyr_user), cdc_acm) && CONFIG_USB_CDC_ACM)
+#if (DT_NODE_HAS_PROP(DT_PATH(zephyr_user), cdc_acm) && (CONFIG_USB_CDC_ACM || CONFIG_USBD_CDC_ACM_CLASS))
   Serial.begin(115200);
 #endif
 

diff --git a/loader/CMakeLists.txt b/loader/CMakeLists.txt
@@ -16,6 +16,11 @@ project(app LANGUAGES C CXX)
 
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/blobs)
 
+# for USB device stack NEXT
+target_sources_ifdef(CONFIG_USB_DEVICE_STACK_NEXT app PRIVATE
+    ${CMAKE_CURRENT_LIST_DIR}/../cores/arduino/usb_device_descriptor.c
+)
+
 FILE(GLOB app_sources *.c)
 target_sources(app PRIVATE ${app_sources})
 

diff --git a/loader/fixups.c b/loader/fixups.c
@@ -39,6 +39,17 @@ SYS_INIT(disable_bootloader_mpu, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAU
 SYS_INIT(disable_mpu_rasr_xn, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
 #endif
 
+#if defined(CONFIG_SOC_STM32H747XX_M7)
+int enable_bkp_access(void)
+{
+	/* Enable access to the backup domain */
+	// HAL_PWR_EnableBkUpAccess();
+	SET_BIT(PWR->CR1, PWR_CR1_DBP);
+	return 0;
+}
+SYS_INIT(enable_bkp_access, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
+#endif
+
 #if defined(CONFIG_BOARD_ARDUINO_GIGA_R1) && defined(CONFIG_VIDEO)
 #include <zephyr/kernel.h>
 #include <zephyr/device.h>

diff --git a/loader/main.c b/loader/main.c
@@ -33,11 +33,31 @@
 #define SKETCH_FLAG_LINKED      0x02
 
 #define TARGET_HAS_USB_CDC_SHELL \
-	DT_NODE_HAS_PROP(DT_PATH(zephyr_user), cdc_acm) && CONFIG_SHELL && CONFIG_USB_DEVICE_STACK
+	DT_NODE_HAS_PROP(DT_PATH(zephyr_user), cdc_acm) && CONFIG_SHELL && (CONFIG_USB_DEVICE_STACK || CONFIG_USB_DEVICE_STACK_NEXT)
 
 #if TARGET_HAS_USB_CDC_SHELL
 const struct device *const usb_dev = DEVICE_DT_GET(DT_PHANDLE_BY_IDX(DT_PATH(zephyr_user), cdc_acm, 0));
 
+#if CONFIG_USB_DEVICE_STACK_NEXT
+#include <zephyr/usb/usbd.h>
+struct usbd_context *usbd_init_device(usbd_msg_cb_t msg_cb);
+int usb_enable(usb_dc_status_callback status_cb)
+{
+	int err;
+	struct usbd_context *_usbd = usbd_init_device(NULL);
+	if (_usbd == NULL) {
+		return -ENODEV;
+	}
+	if (!usbd_can_detect_vbus(_usbd)) {
+		err = usbd_enable(_usbd);
+		if (err) {
+			return err;
+		}
+	}
+	return 0;
+}
+#endif
+
 static int enable_shell_usb(void)
 {
 	bool log_backend = CONFIG_SHELL_BACKEND_SERIAL_LOG_LEVEL > 0;

diff --git a/variants/arduino_giga_r1_stm32h747xx_m7/arduino_giga_r1_stm32h747xx_m7.conf b/variants/arduino_giga_r1_stm32h747xx_m7/arduino_giga_r1_stm32h747xx_m7.conf
@@ -64,3 +64,5 @@ CONFIG_CYW4343W_MURATA_1DX=y
 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048
 CONFIG_BT_RX_STACK_SIZE=4096
 CONFIG_BT_HCI_TX_STACK_SIZE=4096
+
+CONFIG_STM32H7_BOOT_M4_AT_INIT=n
diff --git a/variants/arduino_opta_stm32h747xx_m7/arduino_opta_stm32h747xx_m7.conf b/variants/arduino_opta_stm32h747xx_m7/arduino_opta_stm32h747xx_m7.conf
@@ -90,3 +90,4 @@ CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN=7168
 CONFIG_MBEDTLS_HASH_ALL_ENABLED=y
 CONFIG_MBEDTLS_CMAC=y
 
+CONFIG_STM32H7_BOOT_M4_AT_INIT=n
Original file line number	Diff line number	Diff line change
Expand Up		@@ -90,3 +90,4 @@ CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN=7168
		CONFIG_MBEDTLS_HASH_ALL_ENABLED=y
		CONFIG_MBEDTLS_CMAC=y

		CONFIG_STM32H7_BOOT_M4_AT_INIT=n