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Could someone explain the attached table and how the values are calculated? (the table is taken from the official usb 2.0 specification page 42).
What I could understand is just the relation between the bytes/frame and bytes/second (as in Full Speed the second consists of 1000 frames). But how is the max transfers, the bytes remaining, frame bandwidth per transfer, and the bytes/frame calculated?
But how is the max transfers,
The max transfers is the number of complete packets of the chosen size that can be sent in a frame.
the bytes remaining,
Once you've sent max transfers * frame size, this is the number of bytes that are left over in the frame.
and the bytes/frame calculated?
Bytes/frame are the number of payload bytes sent in the frame, or the number of bytes/transfer * max transfers.
So, if you send one byte, there's 46 bytes in the packet that carries that byte. The max transfers is the number of packets in a frame, which is 1495 bytes, or 1495/46 = 32.5. We're not counting the half-packet, so that becomes 32, which takes up 32*46=1472 bytes. 23 of the 1495 are unused, so that's bytes remaining. Your bytes/frame, since each transfer passed only one byte, is 32*1=32.
