Chapter 3
Hardware
30
Reference Manual
CoreModule 720
Utility Interface
The Utility interface provides three I/O signals on the module and consists of a 5-pin, 0.100" (2.54mm),
single-row header (J22). The E6XXT CPU drives the Power Button and Speaker signals on the Utility
interface. A separate Power Management microprocessor drives the Reset Switch signal.
Table 3-14
provides the signal definitions.
•
Power Button
•
Reset Switch
•
Speaker
Power Button
The Utility header provides a signal for an external Power Button through pins 1 and 2. The Power Button
allows the user to shut down and power on the system. To shut down the system, press and hold the Power
Button for four seconds. Press the Power Button for one second to power on the system.
Reset Switch
Pins 2 and 3 on the Utility header provide the signal for an external reset button, which allows the user to re-
boot the system.
Speaker
The speaker signal provides sufficient signal strength to drive an external 1W 8
Ω
“Beep” speaker at an
audible level through pins 4 and 5 on the Utility header. The speaker signal is driven from an on-board
amplifier and the CPU.
Table 3-14
describes the pin signals of the Utility interface, which provides a 5-pin, single-row header with
0.100" (2.54mm) pitch.
Note:
The shaded table cells denote power or ground. The * symbol indicates the signal is Active Low.
Table 3-14. Utility Interface Pin Signals (J22)
Pin #
Signal
Description
1
PWR_BTN*
External Power Button (Pins 1-2)
2
GND
Ground
3
RESET SW*
External Reset Switch signal (Pins 2-3)
4
5V
+5 Volts Power
5
SPKR_CONN
Speaker Output (Pins 4-5)
