I do ADE7878 interface with stm32f4xx. Basic Initialization always finish. Now I read frequency for PEROID register value. It's came 50Hz. But without power supply I read that register came 50Hz. How it is work functionality.
Do you mean to say that even without any inputs the period register reading is 50Hz?
If there are no zero crossings, most IC's default to the frequency selected in the SELFREQ bit in COMPMODE register.
You can verify this by setting SELFREQ=1 and then reading the PERIOD register with no inputs. The reading should be 60Hz.
Thanks for consider my question & reply. I do SELFREQ register set 1, But It's came constantly 50Hz. Then I check MMODE = 0x1c,after i set MMODE= 0x00; I can't understand why PERIOD register is working constantly. Otherwise any check parts of ADE7878, kindly send information.
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