Freescale Semiconductor TWR-MCF52259-Ethenet User Manual page 109

The Enumeration Process:
5. The available bandwidth is then divided into frames, and the
host controls those frames which contain 1,500 bytes. Every
millisecond a new frame begins. Within the frame, slots are
reserved for isochronous and interrupt devices (up to 90%) so
that they are guaranteed the bandwidth they need. Bulk and
control transfers use whatever space is left.
Transfer 1
Transaction
What happens when a device is connected?
Frame
Transfer 2
Transaction 1 Transaction 2
1500 bytes / 1 Ms
TM
Transfer 3
Transaction 3 Transaction 1