diff --git a/stmhal/Makefile b/stmhal/Makefile
index fc8580829785199d270974634a185049a8ab6e57..2b5c5ffe2809dfa525bc1dc4041db992bf8ab045 100644
--- a/stmhal/Makefile
+++ b/stmhal/Makefile
@@ -55,10 +55,11 @@ LIBS =
 SRC_C = \
 	main.c \
 	system_stm32f4xx.c \
+	stm32f4xx_it.c \
+	stm32f4xx_hal_msp.c \
 
 #	printf.c \
 #	math.c \
-#	stm32fxxx_it.c \
 #	string0.c \
 #	malloc0.c \
 #	systick.c  \
@@ -99,6 +100,8 @@ SRC_S = \
 SRC_HAL = $(addprefix $(HAL_DIR)/src/,\
 	stm32f4xx_hal.c \
 	stm32f4xx_hal_cortex.c \
+	stm32f4xx_hal_rcc.c \
+	stm32f4xx_hal_gpio.c \
 	)
 
 SRC_STMPERIPH = $(addprefix $(STMPERIPH_DIR)/,\
diff --git a/stmhal/boards/PYBOARD4/stm32f4xx_hal_conf.h b/stmhal/boards/PYBOARD4/stm32f4xx_hal_conf.h
new file mode 100644
index 0000000000000000000000000000000000000000..bc13ac2c3af014baf7d92cd2e4c01979a59c87a3
--- /dev/null
+++ b/stmhal/boards/PYBOARD4/stm32f4xx_hal_conf.h
@@ -0,0 +1,392 @@
+/**
+  ******************************************************************************
+  * @file    stm32f4xx_hal_conf.h
+  * @author  MCD Application Team
+  * @version V1.0.1
+  * @date    26-February-2014
+  * @brief   HAL configuration file.
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
+  *
+  * Redistribution and use in source and binary forms, with or without modification,
+  * are permitted provided that the following conditions are met:
+  *   1. Redistributions of source code must retain the above copyright notice,
+  *      this list of conditions and the following disclaimer.
+  *   2. Redistributions in binary form must reproduce the above copyright notice,
+  *      this list of conditions and the following disclaimer in the documentation
+  *      and/or other materials provided with the distribution.
+  *   3. Neither the name of STMicroelectronics nor the names of its contributors
+  *      may be used to endorse or promote products derived from this software
+  *      without specific prior written permission.
+  *
+  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+  *
+  ******************************************************************************
+  */ 
+
+/* Define to prevent recursive inclusion -------------------------------------*/
+#ifndef __STM32F4xx_HAL_CONF_H
+#define __STM32F4xx_HAL_CONF_H
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+/* Exported types ------------------------------------------------------------*/
+/* Exported constants --------------------------------------------------------*/
+
+#define STM32F405xx
+
+/* ########################## Module Selection ############################## */
+/**
+  * @brief This is the list of modules to be used in the HAL driver 
+  */
+#define HAL_MODULE_ENABLED
+#define HAL_ADC_MODULE_ENABLED
+#define HAL_CAN_MODULE_ENABLED
+#define HAL_CRC_MODULE_ENABLED
+#define HAL_CRYP_MODULE_ENABLED
+#define HAL_DAC_MODULE_ENABLED
+#define HAL_DCMI_MODULE_ENABLED
+#define HAL_DMA_MODULE_ENABLED
+/* #define HAL_DMA2D_MODULE_ENABLED */
+#define HAL_ETH_MODULE_ENABLED
+#define HAL_FLASH_MODULE_ENABLED
+#define HAL_NAND_MODULE_ENABLED
+#define HAL_NOR_MODULE_ENABLED
+#define HAL_PCCARD_MODULE_ENABLED
+#define HAL_SRAM_MODULE_ENABLED
+/* #define HAL_SDRAM_MODULE_ENABLED */
+#define HAL_HASH_MODULE_ENABLED
+#define HAL_GPIO_MODULE_ENABLED
+#define HAL_I2C_MODULE_ENABLED
+#define HAL_I2S_MODULE_ENABLED
+#define HAL_IWDG_MODULE_ENABLED
+#define HAL_LTDC_MODULE_ENABLED
+#define HAL_PWR_MODULE_ENABLED
+#define HAL_RCC_MODULE_ENABLED
+#define HAL_RNG_MODULE_ENABLED
+#define HAL_RTC_MODULE_ENABLED
+/* #define HAL_SAI_MODULE_ENABLED */
+#define HAL_SD_MODULE_ENABLED
+#define HAL_SPI_MODULE_ENABLED
+#define HAL_TIM_MODULE_ENABLED
+#define HAL_UART_MODULE_ENABLED
+#define HAL_USART_MODULE_ENABLED
+#define HAL_IRDA_MODULE_ENABLED
+#define HAL_SMARTCARD_MODULE_ENABLED
+#define HAL_WWDG_MODULE_ENABLED
+#define HAL_CORTEX_MODULE_ENABLED
+#define HAL_PCD_MODULE_ENABLED
+#define HAL_HCD_MODULE_ENABLED
+
+
+/* ########################## HSE/HSI Values adaptation ##################### */
+/**
+  * @brief Adjust the value of External High Speed oscillator (HSE) used in your application.
+  *        This value is used by the RCC HAL module to compute the system frequency
+  *        (when HSE is used as system clock source, directly or through the PLL).  
+  */
+#if !defined  (HSE_VALUE) 
+  #define HSE_VALUE    ((uint32_t)8000000) /*!< Value of the External oscillator in Hz */
+#endif /* HSE_VALUE */
+
+#if !defined  (HSE_STARTUP_TIMEOUT)
+  #define HSE_STARTUP_TIMEOUT    ((uint32_t)5000)   /*!< Time out for HSE start up, in ms */
+#endif /* HSE_STARTUP_TIMEOUT */
+
+/**
+  * @brief Internal High Speed oscillator (HSI) value.
+  *        This value is used by the RCC HAL module to compute the system frequency
+  *        (when HSI is used as system clock source, directly or through the PLL). 
+  */
+#if !defined  (HSI_VALUE)
+  #define HSI_VALUE    ((uint32_t)16000000) /*!< Value of the Internal oscillator in Hz*/
+#endif /* HSI_VALUE */
+
+/**
+  * @brief External clock source for I2S peripheral
+  *        This value is used by the I2S HAL module to compute the I2S clock source 
+  *        frequency, this source is inserted directly through I2S_CKIN pad. 
+  */
+#if !defined  (EXTERNAL_CLOCK_VALUE)
+  #define EXTERNAL_CLOCK_VALUE    ((uint32_t)12288000) /*!< Value of the Internal oscillator in Hz*/
+#endif /* EXTERNAL_CLOCK_VALUE */
+
+/* Tip: To avoid modifying this file each time you need to use different HSE,
+   ===  you can define the HSE value in your toolchain compiler preprocessor. */
+
+/* ########################### System Configuration ######################### */
+/**
+  * @brief This is the HAL system configuration section
+  */     
+#define  VDD_VALUE                    ((uint32_t)3300) /*!< Value of VDD in mv */
+#define  USE_RTOS                     0
+#define  PREFETCH_ENABLE              1
+#define  INSTRUCTION_CACHE_ENABLE     1
+#define  DATA_CACHE_ENABLE            1
+
+/* ########################## Assert Selection ############################## */
+/**
+  * @brief Uncomment the line below to expanse the "assert_param" macro in the 
+  *        HAL drivers code
+  */
+/* #define USE_FULL_ASSERT    1 */
+
+/* ################## Ethernet peripheral configuration ##################### */
+
+/* Section 1 : Ethernet peripheral configuration */
+
+/* MAC ADDRESS: MAC_ADDR0:MAC_ADDR1:MAC_ADDR2:MAC_ADDR3:MAC_ADDR4:MAC_ADDR5 */
+#define MAC_ADDR0   2
+#define MAC_ADDR1   0
+#define MAC_ADDR2   0
+#define MAC_ADDR3   0
+#define MAC_ADDR4   0
+#define MAC_ADDR5   0
+
+/* Definition of the Ethernet driver buffers size and count */   
+#define ETH_RX_BUF_SIZE                ETH_MAX_PACKET_SIZE /* buffer size for receive               */
+#define ETH_TX_BUF_SIZE                ETH_MAX_PACKET_SIZE /* buffer size for transmit              */
+#define ETH_RXBUFNB                    ((uint32_t)4)       /* 4 Rx buffers of size ETH_RX_BUF_SIZE  */
+#define ETH_TXBUFNB                    ((uint32_t)4)       /* 4 Tx buffers of size ETH_TX_BUF_SIZE  */
+
+/* Section 2: PHY configuration section */
+
+/* DP83848 PHY Address*/ 
+#define DP83848_PHY_ADDRESS             0x01
+/* PHY Reset delay these values are based on a 1 ms Systick interrupt*/ 
+#define PHY_RESET_DELAY                 ((uint32_t)0x000000FF)
+/* PHY Configuration delay */
+#define PHY_CONFIG_DELAY                ((uint32_t)0x00000FFF)
+
+#define PHY_READ_TO                     ((uint32_t)0x0000FFFF)
+#define PHY_WRITE_TO                    ((uint32_t)0x0000FFFF)
+
+/* Section 3: Common PHY Registers */
+
+#define PHY_BCR                         ((uint16_t)0x00)    /*!< Transceiver Basic Control Register   */
+#define PHY_BSR                         ((uint16_t)0x01)    /*!< Transceiver Basic Status Register    */
+ 
+#define PHY_RESET                       ((uint16_t)0x8000)  /*!< PHY Reset */
+#define PHY_LOOPBACK                    ((uint16_t)0x4000)  /*!< Select loop-back mode */
+#define PHY_FULLDUPLEX_100M             ((uint16_t)0x2100)  /*!< Set the full-duplex mode at 100 Mb/s */
+#define PHY_HALFDUPLEX_100M             ((uint16_t)0x2000)  /*!< Set the half-duplex mode at 100 Mb/s */
+#define PHY_FULLDUPLEX_10M              ((uint16_t)0x0100)  /*!< Set the full-duplex mode at 10 Mb/s  */
+#define PHY_HALFDUPLEX_10M              ((uint16_t)0x0000)  /*!< Set the half-duplex mode at 10 Mb/s  */
+#define PHY_AUTONEGOTIATION             ((uint16_t)0x1000)  /*!< Enable auto-negotiation function     */
+#define PHY_RESTART_AUTONEGOTIATION     ((uint16_t)0x0200)  /*!< Restart auto-negotiation function    */
+#define PHY_POWERDOWN                   ((uint16_t)0x0800)  /*!< Select the power down mode           */
+#define PHY_ISOLATE                     ((uint16_t)0x0400)  /*!< Isolate PHY from MII                 */
+
+#define PHY_AUTONEGO_COMPLETE           ((uint16_t)0x0020)  /*!< Auto-Negotiation process completed   */
+#define PHY_LINKED_STATUS               ((uint16_t)0x0004)  /*!< Valid link established               */
+#define PHY_JABBER_DETECTION            ((uint16_t)0x0002)  /*!< Jabber condition detected            */
+  
+/* Section 4: Extended PHY Registers */
+
+#define PHY_SR                          ((uint16_t)0x10)    /*!< PHY status register Offset                      */
+#define PHY_MICR                        ((uint16_t)0x11)    /*!< MII Interrupt Control Register                  */
+#define PHY_MISR                        ((uint16_t)0x12)    /*!< MII Interrupt Status and Misc. Control Register */
+ 
+#define PHY_LINK_STATUS                 ((uint16_t)0x0001)  /*!< PHY Link mask                                   */
+#define PHY_SPEED_STATUS                ((uint16_t)0x0002)  /*!< PHY Speed mask                                  */
+#define PHY_DUPLEX_STATUS               ((uint16_t)0x0004)  /*!< PHY Duplex mask                                 */
+
+#define PHY_MICR_INT_EN                 ((uint16_t)0x0002)  /*!< PHY Enable interrupts                           */
+#define PHY_MICR_INT_OE                 ((uint16_t)0x0001)  /*!< PHY Enable output interrupt events              */
+
+#define PHY_MISR_LINK_INT_EN            ((uint16_t)0x0020)  /*!< Enable Interrupt on change of link status       */
+#define PHY_LINK_INTERRUPT              ((uint16_t)0x2000)  /*!< PHY link status interrupt mask                  */
+
+/* Includes ------------------------------------------------------------------*/
+/**
+  * @brief Include module's header file 
+  */
+
+#ifdef HAL_RCC_MODULE_ENABLED
+  #include "stm32f4xx_hal_rcc.h"
+#endif /* HAL_RCC_MODULE_ENABLED */
+
+#ifdef HAL_GPIO_MODULE_ENABLED
+  #include "stm32f4xx_hal_gpio.h"
+#endif /* HAL_GPIO_MODULE_ENABLED */
+
+#ifdef HAL_DMA_MODULE_ENABLED
+  #include "stm32f4xx_hal_dma.h"
+#endif /* HAL_DMA_MODULE_ENABLED */
+   
+#ifdef HAL_CORTEX_MODULE_ENABLED
+  #include "stm32f4xx_hal_cortex.h"
+#endif /* HAL_CORTEX_MODULE_ENABLED */
+
+#ifdef HAL_ADC_MODULE_ENABLED
+  #include "stm32f4xx_hal_adc.h"
+#endif /* HAL_ADC_MODULE_ENABLED */
+
+#ifdef HAL_CAN_MODULE_ENABLED
+  #include "stm32f4xx_hal_can.h"
+#endif /* HAL_CAN_MODULE_ENABLED */
+
+#ifdef HAL_CRC_MODULE_ENABLED
+  #include "stm32f4xx_hal_crc.h"
+#endif /* HAL_CRC_MODULE_ENABLED */
+
+#ifdef HAL_CRYP_MODULE_ENABLED
+  #include "stm32f4xx_hal_cryp.h" 
+#endif /* HAL_CRYP_MODULE_ENABLED */
+
+#ifdef HAL_DMA2D_MODULE_ENABLED
+  #include "stm32f4xx_hal_dma2d.h"
+#endif /* HAL_DMA2D_MODULE_ENABLED */
+
+#ifdef HAL_DAC_MODULE_ENABLED
+  #include "stm32f4xx_hal_dac.h"
+#endif /* HAL_DAC_MODULE_ENABLED */
+
+#ifdef HAL_DCMI_MODULE_ENABLED
+  #include "stm32f4xx_hal_dcmi.h"
+#endif /* HAL_DCMI_MODULE_ENABLED */
+
+#ifdef HAL_ETH_MODULE_ENABLED
+  #include "stm32f4xx_hal_eth.h"
+#endif /* HAL_ETH_MODULE_ENABLED */
+
+#ifdef HAL_FLASH_MODULE_ENABLED
+  #include "stm32f4xx_hal_flash.h"
+#endif /* HAL_FLASH_MODULE_ENABLED */
+ 
+#ifdef HAL_SRAM_MODULE_ENABLED
+  #include "stm32f4xx_hal_sram.h"
+#endif /* HAL_SRAM_MODULE_ENABLED */
+
+#ifdef HAL_NOR_MODULE_ENABLED
+  #include "stm32f4xx_hal_nor.h"
+#endif /* HAL_NOR_MODULE_ENABLED */
+
+#ifdef HAL_NAND_MODULE_ENABLED
+  #include "stm32f4xx_hal_nand.h"
+#endif /* HAL_NAND_MODULE_ENABLED */
+
+#ifdef HAL_PCCARD_MODULE_ENABLED
+  #include "stm32f4xx_hal_pccard.h"
+#endif /* HAL_PCCARD_MODULE_ENABLED */ 
+  
+#ifdef HAL_SDRAM_MODULE_ENABLED
+  #include "stm32f4xx_hal_sdram.h"
+#endif /* HAL_SDRAM_MODULE_ENABLED */      
+
+#ifdef HAL_HASH_MODULE_ENABLED
+ #include "stm32f4xx_hal_hash.h"
+#endif /* HAL_HASH_MODULE_ENABLED */
+
+#ifdef HAL_I2C_MODULE_ENABLED
+ #include "stm32f4xx_hal_i2c.h"
+#endif /* HAL_I2C_MODULE_ENABLED */
+
+#ifdef HAL_I2S_MODULE_ENABLED
+ #include "stm32f4xx_hal_i2s.h"
+#endif /* HAL_I2S_MODULE_ENABLED */
+
+#ifdef HAL_IWDG_MODULE_ENABLED
+ #include "stm32f4xx_hal_iwdg.h"
+#endif /* HAL_IWDG_MODULE_ENABLED */
+
+#ifdef HAL_LTDC_MODULE_ENABLED
+ #include "stm32f4xx_hal_ltdc.h"
+#endif /* HAL_LTDC_MODULE_ENABLED */
+
+#ifdef HAL_PWR_MODULE_ENABLED
+ #include "stm32f4xx_hal_pwr.h"
+#endif /* HAL_PWR_MODULE_ENABLED */
+
+#ifdef HAL_RNG_MODULE_ENABLED
+ #include "stm32f4xx_hal_rng.h"
+#endif /* HAL_RNG_MODULE_ENABLED */
+
+#ifdef HAL_RTC_MODULE_ENABLED
+ #include "stm32f4xx_hal_rtc.h"
+#endif /* HAL_RTC_MODULE_ENABLED */
+
+#ifdef HAL_SAI_MODULE_ENABLED
+ #include "stm32f4xx_hal_sai.h"
+#endif /* HAL_SAI_MODULE_ENABLED */
+
+#ifdef HAL_SD_MODULE_ENABLED
+ #include "stm32f4xx_hal_sd.h"
+#endif /* HAL_SD_MODULE_ENABLED */
+
+#ifdef HAL_SPI_MODULE_ENABLED
+ #include "stm32f4xx_hal_spi.h"
+#endif /* HAL_SPI_MODULE_ENABLED */
+
+#ifdef HAL_TIM_MODULE_ENABLED
+ #include "stm32f4xx_hal_tim.h"
+#endif /* HAL_TIM_MODULE_ENABLED */
+
+#ifdef HAL_UART_MODULE_ENABLED
+ #include "stm32f4xx_hal_uart.h"
+#endif /* HAL_UART_MODULE_ENABLED */
+
+#ifdef HAL_USART_MODULE_ENABLED
+ #include "stm32f4xx_hal_usart.h"
+#endif /* HAL_USART_MODULE_ENABLED */
+
+#ifdef HAL_IRDA_MODULE_ENABLED
+ #include "stm32f4xx_hal_irda.h"
+#endif /* HAL_IRDA_MODULE_ENABLED */
+
+#ifdef HAL_SMARTCARD_MODULE_ENABLED
+ #include "stm32f4xx_hal_smartcard.h"
+#endif /* HAL_SMARTCARD_MODULE_ENABLED */
+
+#ifdef HAL_WWDG_MODULE_ENABLED
+ #include "stm32f4xx_hal_wwdg.h"
+#endif /* HAL_WWDG_MODULE_ENABLED */
+
+#ifdef HAL_PCD_MODULE_ENABLED
+ #include "stm32f4xx_hal_pcd.h"
+#endif /* HAL_PCD_MODULE_ENABLED */
+
+#ifdef HAL_HCD_MODULE_ENABLED
+ #include "stm32f4xx_hal_hcd.h"
+#endif /* HAL_HCD_MODULE_ENABLED */
+   
+/* Exported macro ------------------------------------------------------------*/
+#ifdef  USE_FULL_ASSERT
+/**
+  * @brief  The assert_param macro is used for function's parameters check.
+  * @param  expr: If expr is false, it calls assert_failed function
+  *         which reports the name of the source file and the source
+  *         line number of the call that failed. 
+  *         If expr is true, it returns no value.
+  * @retval None
+  */
+  #define assert_param(expr) ((expr) ? (void)0 : assert_failed((uint8_t *)__FILE__, __LINE__))
+/* Exported functions ------------------------------------------------------- */
+  void assert_failed(uint8_t* file, uint32_t line);
+#else
+  #define assert_param(expr) ((void)0)
+#endif /* USE_FULL_ASSERT */    
+    
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __STM32F4xx_HAL_CONF_H */
+ 
+
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
diff --git a/stmhal/main.c b/stmhal/main.c
index 95d8a100210f678f06d08f237f44bd8cd921b9f9..33cf617adc28b76a25a3007fdaa85dcf90f52ef6 100644
--- a/stmhal/main.c
+++ b/stmhal/main.c
@@ -2,6 +2,7 @@
 #include <string.h>
 
 #include <stm32f4xx_hal.h>
+#include <stm32f4xx_hal_gpio.h>
 #if 0
 #include <stm32f4xx.h>
 #include <stm32f4xx_rcc.h>
@@ -162,6 +163,88 @@ static mp_obj_t pyb_help(void) {
 }
 #endif
 
+void led_init(void) {
+    /* GPIO structure */
+    GPIO_InitTypeDef GPIO_InitStructure;
+
+    /* Configure I/O speed, mode, output type and pull */
+    GPIO_InitStructure.Pin = GPIO_PIN_13 | GPIO_PIN_14 | GPIO_PIN_15;
+    GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
+    GPIO_InitStructure.Pull = GPIO_NOPULL;
+    GPIO_InitStructure.Speed = GPIO_SPEED_LOW;
+    GPIO_InitStructure.Alternate = 0; // unused
+
+    /* initialize */
+    HAL_GPIO_Init(GPIOA, &GPIO_InitStructure);
+}
+
+void led_state(int led_id, int state) {
+    HAL_GPIO_WritePin(GPIOA, 1 << (13 + led_id), state);
+}
+
+/**
+  * @brief  System Clock Configuration
+  *         The system Clock is configured as follow : 
+  *            System Clock source            = PLL (HSE)
+  *            SYSCLK(Hz)                     = 168000000
+  *            HCLK(Hz)                       = 168000000
+  *            AHB Prescaler                  = 1
+  *            APB1 Prescaler                 = 4
+  *            APB2 Prescaler                 = 2
+  *            HSE Frequency(Hz)              = 8000000
+  *            PLL_M                          = 8
+  *            PLL_N                          = 336
+  *            PLL_P                          = 2
+  *            PLL_Q                          = 7
+  *            VDD(V)                         = 3.3
+  *            Main regulator output voltage  = Scale1 mode
+  *            Flash Latency(WS)              = 5
+  * @param  None
+  * @retval None
+  */
+static void SystemClock_Config(void) {
+  RCC_ClkInitTypeDef RCC_ClkInitStruct;
+  RCC_OscInitTypeDef RCC_OscInitStruct;
+  
+  /* Enable Power Control clock */
+  __PWR_CLK_ENABLE();
+  
+  /* The voltage scaling allows optimizing the power consumption when the device is 
+     clocked below the maximum system frequency, to update the voltage scaling value 
+     regarding system frequency refer to product datasheet.  */
+  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
+
+  /* Enable HSE Oscillator and activate PLL with HSE as source */
+  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
+  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
+  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
+  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
+  RCC_OscInitStruct.PLL.PLLM = 8;
+  RCC_OscInitStruct.PLL.PLLN = 336;
+  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
+  RCC_OscInitStruct.PLL.PLLQ = 7;
+  if(HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
+  {
+    /* Initialization Error */
+    for (;;) {
+    }
+  }
+  
+  /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 
+     clocks dividers */
+  RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
+  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
+  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;  
+  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;  
+  if(HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
+  {
+    /* Initialization Error */
+    for (;;) {
+    }
+  }
+}
+
 int main(void) {
     // TODO disable JTAG
 
@@ -173,6 +256,32 @@ int main(void) {
        */
     HAL_Init();
 
+    // set the system clock to be HSE
+    SystemClock_Config();
+
+    // enable GPIO clocks
+    __GPIOA_CLK_ENABLE();
+    __GPIOB_CLK_ENABLE();
+    __GPIOC_CLK_ENABLE();
+    __GPIOD_CLK_ENABLE();
+
+    // enable the CCM RAM
+    __CCMDATARAMEN_CLK_ENABLE();
+
+    // some test code to flash LEDs
+    led_init();
+
+    led_state(0, 1);
+    led_state(1, 0);
+    led_state(2, 1);
+
+    for (;;) {
+        HAL_Delay(500);
+        led_state(1, 1);
+        HAL_Delay(500);
+        led_state(1, 0);
+    }
+
 #if 0
 
     // update the SystemCoreClock variable
diff --git a/stmhal/stm32f4xx_hal_msp.c b/stmhal/stm32f4xx_hal_msp.c
new file mode 100644
index 0000000000000000000000000000000000000000..55bf62463a0d8b8f89f84fb1015b03438251f1b2
--- /dev/null
+++ b/stmhal/stm32f4xx_hal_msp.c
@@ -0,0 +1,107 @@
+/**
+  ******************************************************************************
+  * @file    Templates/Src/stm32f4xx_hal_msp.c
+  * @author  MCD Application Team
+  * @version V1.0.1
+  * @date    26-February-2014
+  * @brief   HAL MSP module.
+  *         
+  @verbatim
+ ===============================================================================
+                     ##### How to use this driver #####
+ ===============================================================================
+    [..]
+    This file is generated automatically by MicroXplorer and eventually modified 
+    by the user
+
+  @endverbatim
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
+  *
+  * Redistribution and use in source and binary forms, with or without modification,
+  * are permitted provided that the following conditions are met:
+  *   1. Redistributions of source code must retain the above copyright notice,
+  *      this list of conditions and the following disclaimer.
+  *   2. Redistributions in binary form must reproduce the above copyright notice,
+  *      this list of conditions and the following disclaimer in the documentation
+  *      and/or other materials provided with the distribution.
+  *   3. Neither the name of STMicroelectronics nor the names of its contributors
+  *      may be used to endorse or promote products derived from this software
+  *      without specific prior written permission.
+  *
+  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+  *
+  ******************************************************************************
+  */ 
+
+/* Includes ------------------------------------------------------------------*/
+#include "stm32f4xx_hal.h"
+
+/** @addtogroup STM32F4xx_HAL_Driver
+  * @{
+  */
+
+/** @defgroup HAL_MSP
+  * @brief HAL MSP module.
+  * @{
+  */
+
+/* Private typedef -----------------------------------------------------------*/
+/* Private define ------------------------------------------------------------*/
+/* Private macro -------------------------------------------------------------*/
+/* Private variables ---------------------------------------------------------*/
+/* Private function prototypes -----------------------------------------------*/
+/* Private functions ---------------------------------------------------------*/
+
+/** @defgroup HAL_MSP_Private_Functions
+  * @{
+  */
+
+/**
+  * @brief  Initializes the Global MSP.
+  * @param  None
+  * @retval None
+  */
+void HAL_MspInit(void)
+{
+  /* NOTE : This function is generated automatically by MicroXplorer and eventually  
+            modified by the user
+   */ 
+}
+
+/**
+  * @brief  DeInitializes the Global MSP.
+  * @param  None  
+  * @retval None
+  */
+void HAL_MspDeInit(void)
+{
+  /* NOTE : This function is generated automatically by MicroXplorer and eventually  
+            modified by the user
+   */
+}
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
diff --git a/stmhal/stm32f4xx_it.c b/stmhal/stm32f4xx_it.c
new file mode 100644
index 0000000000000000000000000000000000000000..96b12bfe4a99317aa7b5f7df3f093c2195f45348
--- /dev/null
+++ b/stmhal/stm32f4xx_it.c
@@ -0,0 +1,189 @@
+/**
+  ******************************************************************************
+  * @file    Templates/Src/stm32f4xx_it.c 
+  * @author  MCD Application Team
+  * @version V1.0.1
+  * @date    26-February-2014
+  * @brief   Main Interrupt Service Routines.
+  *          This file provides template for all exceptions handler and 
+  *          peripherals interrupt service routine.
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
+  *
+  * Redistribution and use in source and binary forms, with or without modification,
+  * are permitted provided that the following conditions are met:
+  *   1. Redistributions of source code must retain the above copyright notice,
+  *      this list of conditions and the following disclaimer.
+  *   2. Redistributions in binary form must reproduce the above copyright notice,
+  *      this list of conditions and the following disclaimer in the documentation
+  *      and/or other materials provided with the distribution.
+  *   3. Neither the name of STMicroelectronics nor the names of its contributors
+  *      may be used to endorse or promote products derived from this software
+  *      without specific prior written permission.
+  *
+  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+  *
+  ******************************************************************************
+  */
+
+/* Includes ------------------------------------------------------------------*/
+#include <stdio.h>
+
+#include "stm32f4xx_it.h"
+#include "stm32f4xx_hal.h"
+
+/** @addtogroup STM32F4xx_HAL_Examples
+  * @{
+  */
+
+/** @addtogroup Templates
+  * @{
+  */
+
+/* Private typedef -----------------------------------------------------------*/
+/* Private define ------------------------------------------------------------*/
+/* Private macro -------------------------------------------------------------*/
+/* Private variables ---------------------------------------------------------*/
+
+/* Private function prototypes -----------------------------------------------*/
+/* Private functions ---------------------------------------------------------*/
+
+/******************************************************************************/
+/*            Cortex-M4 Processor Exceptions Handlers                         */
+/******************************************************************************/
+
+/**
+  * @brief   This function handles NMI exception.
+  * @param  None
+  * @retval None
+  */
+void NMI_Handler(void)
+{
+}
+
+/**
+  * @brief  This function handles Hard Fault exception.
+  * @param  None
+  * @retval None
+  */
+void HardFault_Handler(void)
+{
+  /* Go to infinite loop when Hard Fault exception occurs */
+  while (1)
+  {
+  }
+}
+
+/**
+  * @brief  This function handles Memory Manage exception.
+  * @param  None
+  * @retval None
+  */
+void MemManage_Handler(void)
+{
+  /* Go to infinite loop when Memory Manage exception occurs */
+  while (1)
+  {
+  }
+}
+
+/**
+  * @brief  This function handles Bus Fault exception.
+  * @param  None
+  * @retval None
+  */
+void BusFault_Handler(void)
+{
+  /* Go to infinite loop when Bus Fault exception occurs */
+  while (1)
+  {
+  }
+}
+
+/**
+  * @brief  This function handles Usage Fault exception.
+  * @param  None
+  * @retval None
+  */
+void UsageFault_Handler(void)
+{
+  /* Go to infinite loop when Usage Fault exception occurs */
+  while (1)
+  {
+  }
+}
+
+/**
+  * @brief  This function handles SVCall exception.
+  * @param  None
+  * @retval None
+  */
+void SVC_Handler(void)
+{
+}
+
+/**
+  * @brief  This function handles Debug Monitor exception.
+  * @param  None
+  * @retval None
+  */
+void DebugMon_Handler(void)
+{
+}
+
+/**
+  * @brief  This function handles PendSVC exception.
+  * @param  None
+  * @retval None
+  */
+void PendSV_Handler(void)
+{
+}
+
+/**
+  * @brief  This function handles SysTick Handler.
+  * @param  None
+  * @retval None
+  */
+void SysTick_Handler(void)
+{
+  HAL_IncTick();
+}
+
+/******************************************************************************/
+/*                 STM32F4xx Peripherals Interrupt Handlers                   */
+/*  Add here the Interrupt Handler for the used peripheral(s) (PPP), for the  */
+/*  available peripheral interrupt handler's name please refer to the startup */
+/*  file (startup_stm32f4xx.s).                                               */
+/******************************************************************************/
+
+/**
+  * @brief  This function handles PPP interrupt request.
+  * @param  None
+  * @retval None
+  */
+/*void PPP_IRQHandler(void)
+{
+}*/
+
+
+/**
+  * @}
+  */ 
+
+/**
+  * @}
+  */
+
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
diff --git a/stmhal/stm32f4xx_it.h b/stmhal/stm32f4xx_it.h
new file mode 100644
index 0000000000000000000000000000000000000000..c2aabfadd03b0213550e87bca2a94a4323f05842
--- /dev/null
+++ b/stmhal/stm32f4xx_it.h
@@ -0,0 +1,68 @@
+/**
+  ******************************************************************************
+  * @file    Templates/Inc/stm32f4xx_it.h 
+  * @author  MCD Application Team
+  * @version V1.0.1
+  * @date    26-February-2014
+  * @brief   This file contains the headers of the interrupt handlers.
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
+  *
+  * Redistribution and use in source and binary forms, with or without modification,
+  * are permitted provided that the following conditions are met:
+  *   1. Redistributions of source code must retain the above copyright notice,
+  *      this list of conditions and the following disclaimer.
+  *   2. Redistributions in binary form must reproduce the above copyright notice,
+  *      this list of conditions and the following disclaimer in the documentation
+  *      and/or other materials provided with the distribution.
+  *   3. Neither the name of STMicroelectronics nor the names of its contributors
+  *      may be used to endorse or promote products derived from this software
+  *      without specific prior written permission.
+  *
+  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+  *
+  ******************************************************************************
+  */
+
+/* Define to prevent recursive inclusion -------------------------------------*/
+#ifndef __STM32F4xx_IT_H
+#define __STM32F4xx_IT_H
+
+#ifdef __cplusplus
+ extern "C" {
+#endif 
+
+/* Includes ------------------------------------------------------------------*/
+/* Exported types ------------------------------------------------------------*/
+/* Exported constants --------------------------------------------------------*/
+/* Exported macro ------------------------------------------------------------*/
+/* Exported functions ------------------------------------------------------- */
+
+void NMI_Handler(void);
+void HardFault_Handler(void);
+void MemManage_Handler(void);
+void BusFault_Handler(void);
+void UsageFault_Handler(void);
+void SVC_Handler(void);
+void DebugMon_Handler(void);
+void PendSV_Handler(void);
+void SysTick_Handler(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __STM32F4xx_IT_H */
+
+/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/