USB DCD on STM32H5 - HardFault after calling HAL_PCD_Start()

[el_uho]

As the title says.

I am using STM32H523RCT6 with no RTOS (no ThreadX) and USBX in Standalone mode.

The code is basically:

MX_USB_PCD_Init();

MX_USBX_Device_Init();

HAL_PCD_Start(&hpcd_USB_DRD_FS);

Which executes, but as soon as the USB_DRD_FS_IRQHandler is called, I run into a hard fault. The trace is:

USB_DRD_FS_IRQHandler()

HAL_PCD_IRQHandler

HAL_PCD_ResetCallback

_ux_dcd_stm32_initialize_complete

at

/* Create the default control endpoint attached to the device.

Once this endpoint is enabled, the host can then send a setup packet

The device controller will receive it and will call the setup function

module. */

dcd -> ux_slave_dcd_function(dcd, UX_DCD_CREATE_ENDPOINT,

(VOID *) &device -> ux_slave_device_control_endpoint);

the USB_FNR register shows LSOF 0x3 as well as the LCK and RXDP bit set and the USB_ISTR has the bits ESOF, SOF, RST_DCON and SUSP set.

Please help, I've already lost way too much time on this.

[FBL]

Hi @el_uho 

Do you reproduce using promotional boards (like NUCLEO-H563ZI, NUCLEO-H533RE) ? If so, do you reproduce starting with example firmware provided? If not, check your hardware setup and compare with schematics provided.

[el_uho]

Hi!

No, I tried using this example: https://github.com/STMicroelectronics/STM32CubeH5/tree/main/Projects/STM32H573I-DK/Applications/USBX/Ux_Device_MSC and removing the ThreadX stuff because I'm not using RTOS.

I am using a custom hardware that is proven to be working (CDC virtual com port works).

I got past the Hard Fault now by piecing together some code from the example that I was missing (code from the USBX_APP_Device_Init() function and app_ux_device_thread_entry code) and am now facing a "Device not recognized, failed to get device descriptors" error when attaching to PC. 

The USBD_ChangeFunction(ULONG Device_State) is called multiple times after attaching to the Host PC but with unknown states (not present in ux_api.h File) like 0xF4 and 0xF3 and 0xF0.

[el_uho · Accepted solution]

I got it working.

This is one of the posts that helped: https://community.st.com/t5/stm32-mcus-embedded-software/usbx-device-msc-in-standalone-mode/m-p/819314/highlight/true#M65478 

where the 

_ux_device_class_storage_disk_wait

function must me modified -> this should be addressed by ST, since the error is in MX-generated code.

Additionally, this thread helped: https://community.st.com/t5/stm32-mcus/how-to-implement-usbx-in-standalone-mode/ta-p/614435 because the call to 

ux_device_stack_tasks_run();

was missing in my code - shouldn't this call be somehow generated by MX?

Additionally, I had to modify the

UINT MX_USBX_Device_Init(VOID)

function to include

MX_USB_PCD_Init();

HAL_PCDEx_PMAConfig(&hpcd_USB_DRD_FS, 0x00, PCD_SNG_BUF, 0x40);
HAL_PCDEx_PMAConfig(&hpcd_USB_DRD_FS, 0x80, PCD_SNG_BUF, 0x80);
HAL_PCDEx_PMAConfig(&hpcd_USB_DRD_FS, USBD_MSC_EPOUT_ADDR, PCD_SNG_BUF, 0xC0);
HAL_PCDEx_PMAConfig(&hpcd_USB_DRD_FS, USBD_MSC_EPIN_ADDR, PCD_SNG_BUF, 0x2C0);

_ux_dcd_stm32_initialize((ULONG)USB_DRD_FS, (ULONG)&hpcd_USB_DRD_FS);

HAL_PCD_Start(&hpcd_USB_DRD_FS);

in this particular order...

[FBL]

Hi @el_uho 

Would you share your firmware to check with you in standalone mode.

[el_uho]

Hi,

no, I can't publicly share the code. The USB part is woven into some proprietary code that cannot be shared. 

[FBL]

Hi @el_uho 

Thank you for bringing this to our attention. I have tracked this internally for fix. (216585 internal ticket number just for internal tracking).