ETX-CN700
Appendix 1
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3V backup cell input. BATT is typically connected to a 3V lithium backup cell for RTC operation and CMOS
register non-volatility in the absence of system power. When RTC operation is not required by the application,
some ETX modules can back up CMOS contents to EEPROM so a battery is not needed.
I2CLK, I2DAT
These clock and data lines implement an I2C-bus.which supports external slave devices only. Data rate is
approximate 1-10kHz.. This interface is intended for support of EEPROMs and other simple I/O-devices
SMBDATA, SMBCLK
System Management Bus clock and data lines. May be used to support external SMBUS devices such as
temperature and battery monitoring chips. The addresses of external SMBUS devices must be chosen so they do
not conflict with addresses used internally on the ETX module.
KBINH
Keyboard Inhibit. Asserting this pin disables data input from the keyboard.
OVCR#
Over-current detect input. Used to monitor the USB power over-current. Pull with open collector to GND if
over-current is detected.