Kontron COMe Ref. Carrier T2 - Manual (Page 46)

COM Express™ miniBaseboard Type 2 / Connectors and Features
41
16 VCC_RTC 3V-I
3V backup cell input. Should be connected to a 3V backup cell for RTC operation and
storage register non-volatility in the absence of system power. (VBATT = 2.4 – 3.3V)
17 #THRM 3.3V-I Input from off-module temperature sensor indicating an over temperature situation
18 GND GND Ground
19 PWR_OK 3.3V-I
High active input indicating that power from the power supply is ready. It can also
be used as low active reset input signal.
20 GND GND Ground
21 #PWRBTN 3.3V-I Power Button Input. This input is used to support the ACPI Power Button function.
22 GND GND Ground
23 #ATA_ACT 3.3V-O Low active output signal, which indicates activity on IDE interfaces.
24 #CB_RESET 3.3V-O Low active Reset output from module to carrier board