Preliminary - Information Subject to Change - 9/24/98
EZ-USB Development Kit Overview
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USB device even before the 8051 is running. This allows the USB
host to download code into EZ-USB RAM, and then start the 8051.
The enhanced core simplifies 8051 code by implementing much of
the USB protocol.
EZ-USB chips operate at 3.3 volts. This simplifies the design of
bus-powered USB devices, since the 5V power available in the
USB connector (which the USB specification allows to be as low as
4.4V) can drive a 3.3 volt regulator to deliver clean isolated power
to the EZ-USB chip.
The AN2131Q, an 80-pin version of the EZ-USB family has in
addition to the 24 IO pins, a 16-bit address bus and 8-bit data bus
for external memory expansion.
A special “fast transfer” mode moves data directly between external
logic and internal USB FIFOs. The fast transfer mode, along with
abundant endpoint resources, allows the EZ-USB family to support
transfer bandwidths beyond the maximum required by the USB
specification.
Final EZ-USB
System Block
Diagram
Your final USB application most likely will consist of a few major
pieces: a custom Windows USB device driver, the standard
Windows USB drivers, EZ-USB Application firmware, and an
optional custom Windows USB Application program.
Figure 1-2 shows a typical EZ-USB Peripheral application block
diagram.
