My application requires a energy meter so i interface a ATM90E32AS energy meter IC with dsPIC microcontroller. when i gone through the data sheet it was really confusing about power calculation. As per the data sheet power registers are 32 bits wide. There is MSB register and LSB register for active/reactive/apparent power. My confusion is whether MSB and LSB of power registers are 32 bits wide each or both MSB and LSB of power registers combinedly 32 bits wide? And what is complement means which is shown in the comment section? The power register values are attached as image.
The application note for this chip at:
Provides a sample calculation that I think will make this clear for you: