Hello again @EBrun
Concerning your question about the OTG->CID register value meaning :
**The OTG_CID register is a 32-bit register in the USB On-The-Go (OTG) core of a microcontroller that contains the product ID of the USB controller as its reset value.
The product ID is a unique identifier that is assigned by the manufacturer of the USB controller and is used to differentiate it from other similar products.
The reset value of the OTG_CID register is 0x00002300, which means that when the microcontroller is reset, the OTG_CID register is set to this value.
This value corresponds to the product ID of the USB controller, which is a unique value that is assigned by the manufacturer.
By having the product ID as the reset value of the OTG_CID register, it ensures that the USB controller can be uniquely identified by software during initialization.
During the operation of the USB controller, the OTG_CID register may be read by software to obtain the product ID of the USB controller.
This can be useful in certain applications where it is necessary to differentiate between different USB controllers or to perform specific operations based on the product ID.
It is important to note that the value of the OTG_CID register should not be modified during normal operation of the USB controller,
as it may cause unexpected behavior or communication errors. Any modifications to the OTG_CID register should only be performed during initialization
or configuration of the USB controller, and should be done carefully to avoid any unintended consequences.
**The "__HAL_RCC_USB_OTG_FS_CLK_ENABLE()" function is a macro which is used to enable the clock for the USB OTG FS peripheral. When the macro is executed,
it sets a bit in a register of the RCC peripheral that controls the clock enable/disable state of the USB OTG FS peripheral.
**Concerning the line of code that you replaced :
if(((USBx->CID & (0x1U << 8)) == 0U) && (hpcd->Init.battery_charging_enable == 1U))::
This line means :
The first condition checks whether a bit in the USBx->CID register is clear (equal to 0). The bit being checked is the one at position 8, which is shifted by 1 bit to the left (0x1U << 8).
If this condition is true, it means that the USB device is not connected to a charger.
The second condition checks whether the "battery_charging_enable" flag in the PCD_HandleTypeDef structure is set to 1.This flag is used to enable or disable the battery charging feature of the USB controller.
If both conditions are true, the code inside the if statement will be executed, otherwise, it will be skipped.
**if((hpcd->Init.phy_itface != USB_OTG_ULPI_PHY) && (hpcd->Init.battery_charging_enable == 1U))
The first condition checks whether the "phy_itface" member of the PCD_HandleTypeDef structure is not equal to "USB_OTG_ULPI_PHY".
This member is used to select the USB physical interface used by the controller,
and "USB_OTG_ULPI_PHY" refers to the UTMI+ Low Pin Interface (ULPI) PHY.
The second condition checks whether the "battery_charging_enable" member of the PCD_HandleTypeDef structure is set to 1.
This member is used to enable or disable the battery charging feature of the USB controller.
The USB physical interface is the physical layer of the USB communication protocol, which is responsible for transmitting data over the USB cable.
It includes the USB connector,the cable, and the electronics that transmit and receive data between the USB host and the USB device.
The USB controller is a device that manages the USB communication between the USB host and the USB device.
It includes a physical interface that is designed to be compatible with a specific USB physical interface specification,
such as USB 1.x, USB 2.0, or USB 3.x. The physical interface is responsible for encoding and decoding the data transmitted
over the USB cable, and for managing the electrical signals required for the USB communication.
The physical interface used by the USB controller is determined by the design of the USB controller and is specified in the datasheet
or documentation of the controller. Different physical interfaces have different electrical and functional characteristics,
and may be compatible with different USB devices or host controllers. For example, some USB controllers may use the UTMI+ Low Pin Interface (ULPI) PHY,
while others may use the High-Speed Inter-Chip (HSIC) PHY, depending on the requirements of the specific USB application.
This is my first analysis I will keep investigating this issue and I will keep you posted with updates.
Thanks for sharing you *ioc file with me .
Ghofrane
