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some questions about stm32f303cb usb module

Question asked by tag.aseok on Nov 9, 2016
Hello
I have some questions about stm32f303cb usb module:
1- If the EP0 receive buffer is set to 1 bytes, how will received data be handled during setup packet reception (bmRequestType, bRequest,... totaling 8 bytes)?
Will they be stored in adjacent memory space? will a CTR_RX flag set for every byte reception?
2- If EP0 transmit buffer is set to 1 bytes, how will multiple data bytes transmitted to host? will a CTR_TX flag set for every byte transmission?
Suppose it is to send 8 bytes of data with a 1 byte buffer, the first byte is written in dedicated PMA address and endpoint status is set to valid, then this byte will be transmitted, how and when to update the buffer with 2nd,3rd,.. bytes?
3- What will happen if dedicated packet buffer memory is exceeded? (as i inspected there is no problem writing to USB_ADDRn_TX and USB_COUNTn_TX registers)

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