Constant aw_fel::AW_USB_MAX_BULK_SEND

const AW_USB_MAX_BULK_SEND: usize

AW_USB_MAX_BULK_SEND and the timeout constant USB_TIMEOUT are related. Both need to be selected in a way that transferring the maximum chunk size with (SoC-specific) slow transfer speed won't time out.

The 512 KiB here are chosen based on the assumption that we want a 10 seconds timeout, and "slow" transfers take place at approx. 64 KiB/sec, so we can expect the maximum chunk being transmitted within 8 seconds or less.