Ampro LittleBoard 550, Reference Manual

Page: 53 / 100

Chapter 3 Hardware
LittleBoard 550 Reference Manual 47
Utility Interfaces
The Utility interfaces consists of three connectors that provide the standard interface signals, which
include the:
•
Utility 1
♦
Keyboard
♦
External battery connection
♦
Reset Switch
♦
PC Speaker
• Utility 2
♦
PS/2 Mouse
♦
SMBus signals
♦
USB signals for USB ports 1 and 2
♦
Power button signal
•
Utility 3
♦
USB signals for USB ports 3 (USB0) and 4 (and USB1)
Utility 1 Interface (J16)
Utility 1 interface consists of a 16-pin connector and is used to interface the various utility signals to an
external board with external connections or directly to the respective connector, such as, a keyboard,
speaker, etc. Table 3-17 gives the pin outs and interface signals for the Utility 1 interface.
•
Keyboard
•
Battery
•
Reset Switch
•
Speaker
Keyboard Interface
The signal lines for the PS/2 keyboard are provided through the Utility 1 interface (J16), which is also
fully PC/AT compatible.
External Battery
An external battery input connection is provided through the Utility 1 interface (J16) for the Real Time
Clock’s operation in the event the on-board battery is not used.
Reset Switch
The signal lines for a reset switch (hard or soft) are provided through the Utility 1 interface (J16).
NOTE
To perform the equivalent of a power-on reset, the reset button
must be pressed and held for a minimum of three seconds.
PC Speaker
The signal lines for a speaker port with 0.1-watt drive are provided through a Utility 1 interface (J16).