你截图的文字有点问题，是这样的：
In low, medium, high and XL-density devices, the USB and CAN share a dedicated 512-byte
SRAM memory for data transmission and reception, and so they cannot be used
concurrently (the shared RAM is accessed through CAN and USB exclusively). The USB
and CAN can be used in the same application but not at the same time.
换言之，对于F1系列，只有F105/107带双CAN的才不需要USB/CAN共享RAM缓冲区。
In low, medium, high and XL-density devices, the USB and CAN share a dedicated 512-byte
SRAM memory for data transmission and reception, and so they cannot be used
concurrently (the shared RAM is accessed through CAN and USB exclusively). The USB
and CAN can be used in the same application but not at the same time.
换言之，对于F1系列，只有F105/107带双CAN的才不需要USB/CAN共享RAM缓冲区。