Ampro LittleBoard 800, Reference Manual

Page: 53 / 96

Chapter 3 Hardware
LittleBoard 800 Reference Manual 47
Table 3-17. SMBus Reserved Addresses
Component Address Binary
SDRAM EPROM 1010,000x
b
Clock Generator (ICS950811) 1101,001x
b
I/O Hub (82801DBM) 0000,000x
b
(default) Programmable Master
USB Signals (USB1 and USB2)
The LittleBoard 800 contains one root USB hub with four functional USB ports. This connector
(Utility 2) provides two of the four USB ports (USB1 and USB2). The hub is USB V2.0 and Universal
UHCI V1.1 compatible.
Features implemented in the USB ports include the following:
•
Provides two root USB hubs
•
Provides up to four USB ports
•
Supports USB v2.0 and Universal UHCI v1.1
•
Integrated physical layer transceivers
•
Over-current detection status (software) on all four USB ports
NOTE Ampro does not recommend connecting a USB boot device to the
LittleBoard 800 through an external hub. Instead, connect the USB
boot device directly to the LittleBoard 800. Refer to Chapter 4, BIOS
Setup for more information.
Mouse Interface
The signal lines for a PS/2 mouse are provided through the Utility 2 interface (J13).
I
nfrared Port (IrDA)
The Infrared Data Association (IrDA) port provides a two-way wireless communications port using
infrared as a transmission medium at the basic level. There are two basic infrared implementations
provided; the Hewlett-Packard Serial Infrared (HPSIR) and the Amplitude Shift Keyed Infrared
(ASKIR) methods. HPSIR is a serial implementation of infrared developed by Hewlett-Packard. The
IrDA (HPSIR and ASKIR) signals are available on the Utility 2 connector.
The HPSIR method allows serial communication at baud rates up to 115k baud. Each word is sent
serially beginning with a zero value start bit. A zero is sent when a single infrared pulse is sent at the
beginning of the serial bit time. A one is sent when no infrared pulse is sent during the bit time.
The Amplitude Shift Keyed infrared (ASKIR) allows serial communication at baud rates up to 19.2k
baud. Each word is sent serially beginning with a zero value start bit. A zero is sent when a 500kHz
waveform is sent for the duration of the serial bit time. A one is sent when no transmission is sent
during the serial bit time.
Both of these methods require an understanding of the timing diagrams provided in the Super I/O-1
controller chip (LPC47B272) specifications available from the manufacture’s web site and referenced
earlier in this manual. For more information, refer to the SMSC LPC47B272 chip databook and the
Infrared Data Association web site at
http://www.irda.org .
NOTE
For faster speeds and infrared applications not covered in this brief description,
refer to the LPC47B272 chip specifications by Standard Microsystems Corp.