at43usb321 ATMEL Corporation, at43usb321 Datasheet - Page 2

• Manufacturer Part Number: at43usb321
• Description: Full-speed Usb Hub/function Microcontroller
• Manufacturer: ATMEL Corporation

Figure 1. AT43USB321 Block Diagram
Development Support
The AT4USB321 uses the same program and development
tools as the Atmel AVR microcontrollers including: C com-
pilers, macro assemblers, program debuggers/simulators,
in-circuit emulators. The AT43USB321 is binary compatible
with the AT43320 and the two share the same develop-
ment kit, which includes firmware source code for the most
common USB applications.
Applications
The attached diagram shows an application of the
AT43USB321 in a monitor as a hub with two embedded
functions: a monitor display controller and IR receiver. The
number of external downstream ports of the hub is pro-
2
AT43USB321
PD0/RXD
PD2/INT0
PD3/INT1
PD1/TXD
PB[0:7]
PA[0:7]
OSC1
OSC2
6/12M
CEXT
DM0
VCC
VSS
DP0
LFT
CONTROLLER
REPEATER
INTERFACE
HUB AND
DEVICE
ENGINE
SERIAL
HUB
OSC
PLL
&
GENERAL PURPOSE IO
grammable from one to four. The hub can be self-powered
or bus-powered. In most cases, hubs in the monitors will be
self-powered because of the readily availability of the
power supply and its more versatility.
In this example, the AT43USB321 interfaces to the moni-
tor’s microcontroller, the host microcontroller, through an
I
as DDC2Bi. The firmware inside the AT43USB321 acts as
the translator between the host system and the host micro-
controller. This function can be performed without any
modification in the host microcontroller’s firmware resulting
in a very flexible way of adding USB capability in any moni-
tor. The IR receiver function is also implemented in
firmware also and can support any consumer type IR proto-
col that uses a frequency in the range of up to 52 kHz.
2
C serial bus that supports two way communications such
PORT3
PORT2
PORT1
PORT4
DP4
DM4
DP3
DM3
DP2
DM2
DP1
DM1
OVC
PWR
RST