Freescale Semiconductor TWR-MCF52259-Ethenet manual Software General

Concepts

The General USB Process

The Enumeration Process:What happens when a device is connected?

1.Enumeration -Upon powering up, the host: queries all connected devices to determine the requirements of each (such as, class of device power source, number and types of endpoints) and assigns a unique address for each. This same process occurs for devices that are dynamically “plugged in” to the host except the host waits ~120ms for the device to settle.

Software – General

What device class are you?

Do you supply the power or do I?

How many and of what type of endpoints do you need?

TM

Host

Here is your unique address.

What transfer mode do you want?