The NV components (non-volatile) are the components which values can be recorded in an EEPROM device’s non-volatile memory. Whenever the device is restarted or the power is down, the values of NV components remain saved. The device has three types of NV components, broken down by the types of variables they support, which include:
- Boolean variables: NVBooleanWritable component;
- Integer variables: NVIntegerWritable component;
- Numeric (float) variables: NVNumericWritable component.
NV components can operate in the Auto mode (the In slot values are transferred to the Out slot) or in the Hand mode (the Out value is entered manually by the user and cannot be changed by the application).
There are available 512 memory cells for numeric (float/numeric and integer) values and 1536 memory cells for Boolean values in the iSMA-B-AAC20 controllers. NVNumeric and NVInteger components use one numeric cell memory for the Out value and one Boolean memory cell for the Auto/Hand switch mode. NVBoolean components use two Boolean memory cells, one for the Out value and one for the Auto/Hand switch mode.
Since the values of the components are not stored in the Sedona application but in the non-volatile memory of the device, when an application is copied between two devices, output values are not saved and will assume the values stored in the local EEPROM memory. To copy NV components to another device along with their values (e.g., setpoint), use global actions of the plat component:
Step 1: Use global actions CopyFromNvToDefault / CopyFromNvToUser;
Step 2: Save the application and copy it to another device;
Step 3: Use global actions on the target device CopyFromDefaultToNv / CopyFromUserToNv.