User`s manual

48 CMX34GS cpuModule BDM-610000082 Rev A
Optional RTC Battery Input (CN13)
The optional RTC battery input is the connection for an external backup battery. This battery is used by the
cpuModule when system power is removed in order to preserve the date and time of the real time clock.
Connecting a battery is only required to maintain time when power is completely removed from the cpuModule.
A battery is not required for board operation.
Table 28 Optional RTC Battery Input (CN13)
Pin Signal Function
1 BAT RTC Battery Input
2GNDGround
WARNING This optional RTC battery connector (CN13) should be left unconnected if the Utility Port
2.0 connector (CN5) has a battery connected.