I'm developing measuring system with ADE7880. What is a physical address for AFVAR, BFVAR, CFVAR registers?
I can read them out only with HSDC interface?
Yes. They are accessible via HSDC interface alone. However, you can read FVAR register (0xE883) via I2C or SPI and set it up to get fundamental reactive powers, one phase at a time. Or, you read fundamental reactive energy results from addresses 0xE409 - 0xE40B and get average power from that.
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