diff --git a/ports/stm32/boards/NUCLEO_F767ZI/board_init.c b/ports/stm32/boards/NUCLEO_F767ZI/board_init.c
new file mode 100644
index 000000000..7d25a445d
--- /dev/null
+++ b/ports/stm32/boards/NUCLEO_F767ZI/board_init.c
@@ -0,0 +1,8 @@
+#include "py/mphal.h"
+
+void NUCLEO_F767ZI_board_early_init(void) {
+    // Turn off the USB switch
+    #define USB_PowerSwitchOn pin_G6
+    mp_hal_pin_output(USB_PowerSwitchOn);
+    mp_hal_pin_low(USB_PowerSwitchOn);
+}
diff --git a/ports/stm32/boards/NUCLEO_F767ZI/mpconfigboard.h b/ports/stm32/boards/NUCLEO_F767ZI/mpconfigboard.h
index 7de4c3363..3f23d77d4 100644
--- a/ports/stm32/boards/NUCLEO_F767ZI/mpconfigboard.h
+++ b/ports/stm32/boards/NUCLEO_F767ZI/mpconfigboard.h
@@ -13,6 +13,9 @@
 #define MICROPY_HW_ENABLE_DAC       (1)
 #define MICROPY_HW_ENABLE_USB       (1)
 
+#define MICROPY_BOARD_EARLY_INIT    NUCLEO_F767ZI_board_early_init
+void NUCLEO_F767ZI_board_early_init(void);
+
 // HSE is 25MHz
 // VCOClock = HSE * PLLN / PLLM = 25 MHz * 432 / 25 = 432 MHz
 // SYSCLK = VCOClock / PLLP = 432 MHz / 2 = 216 MHz
diff --git a/ports/stm32/boards/NUCLEO_F767ZI/pins.csv b/ports/stm32/boards/NUCLEO_F767ZI/pins.csv
index 9df4fc7ef..3cae615da 100644
--- a/ports/stm32/boards/NUCLEO_F767ZI/pins.csv
+++ b/ports/stm32/boards/NUCLEO_F767ZI/pins.csv
@@ -58,6 +58,7 @@ USB_VBUS,PA9
 USB_ID,PA10
 USB_DM,PA11
 USB_DP,PA12
+USB_POWER,PG6
 VCP_TX,PD8
 VCP_RX,PD9
 UART2_TX,PD5
diff --git a/ports/stm32/boards/NUCLEO_H743ZI/board_init.c b/ports/stm32/boards/NUCLEO_H743ZI/board_init.c
index 1a6006c28..04149c37b 100644
--- a/ports/stm32/boards/NUCLEO_H743ZI/board_init.c
+++ b/ports/stm32/boards/NUCLEO_H743ZI/board_init.c
@@ -1,15 +1,8 @@
-#include STM32_HAL_H
+#include "py/mphal.h"
 
 void NUCLEO_H743ZI_board_early_init(void) {
-    GPIO_InitTypeDef GPIO_InitStructure;
-
-    __HAL_RCC_GPIOG_CLK_ENABLE();
-
     // Turn off the USB switch
-    GPIO_InitStructure.Pin = GPIO_PIN_6;
-    GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
-    GPIO_InitStructure.Pull = GPIO_PULLDOWN;
-    GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_LOW;
-    HAL_GPIO_Init(GPIOG, &GPIO_InitStructure);
-    HAL_GPIO_WritePin(GPIOG, GPIO_PIN_6, GPIO_PIN_RESET);
+    #define USB_PowerSwitchOn pin_G6
+    mp_hal_pin_output(USB_PowerSwitchOn);
+    mp_hal_pin_low(USB_PowerSwitchOn);
 }