Tomas Cerskus
USB device stack with Nucleo F401RE support. NOTE: the default clock config needs to be changed to in order for USB to work.
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USBDevice
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Tomas Cerskus
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Slightly modified original USBDevice library to support F401RE.
On F401RE the USB connector should be attached to PA12 (D+), PA11(D-), PA9(+5V).
F401RE requires 48MHz clock for USB. Therefore in order for this to work you will need to change the default clock settings:
Clock settings for USB
#include "stm32f4xx_hal.h"
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.LSEState = RCC_LSE_ON; /* External 32.768 kHz clock on OSC_IN/OSC_OUT */
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLM = 16;
RCC_OscInitStruct.PLL.PLLN = 336;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4;
RCC_OscInitStruct.PLL.PLLQ = 7;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
error("RTC error: LSI clock initialization failed.");
}
NOTE: Changing the clock frequency might affect the behavior of other libraries. I only tested the Serial library.
If this does not work, most likely the clock has not been configured correctly. Make sure you have updated your MBED library to the latest version (older version used LSI clock, and above code is for LSE).