Battery and Voltage

The Coin Cell battery (CR2354) holds up the contents of the Battery-backed SRAM and the Real-time clock for at least 5 years. It is discussed in section CPU-Battery.

The voltage level of this battery can be read by the project.

In addition, a variable that is a flag will trip when the Battery is low, which occurs at 2.9 volts. Even in a low voltage condition, the battery will continue to support the Battery Backed SRAM for a few days after this flag goes active.

The variables are- byBatteryIsVoltageTooLow, uiBatteryCurrentVoltage.

Variable Access

To access these variables, install the device P2CDS622_SystemTags, by right-clicking on Device and Add Device > Miscellaneous.

Add this device and then connect to the P2CDS-622.

To access these variables you can assign them as Global Vars by naming the variable in the IO Mapping sections as shown below. Then access the variables as you see fit.

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Alternatively, you can create a variable in your program/Application and assign that variable in the IO Mapping sections as shown below.

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