32 I2C Relay
I make small project to controll 32 relay by I2C expander PCF8574 .
In my project are V_LIGHT for relay control and V_TEMP to define if want save relay state to eeprom memory or not .
if S_TEMP is 0 then after reset, all relay are close and clear eeprom memory for relay state , if S_TEMP is 1 then relay state are read from memory .. and save state to memory if change state of relay .
V_LIGHT not define if relay is open or close .. only change state from 1 to 0 , and 0 to 1 .
It's to control light in my house ..
PS: tested in Arduino Nano (china clone CH340 with micro USB ) , nrf24L01+ (PCB antenna) with 1x PFC8574
PPS: Node ID is manualy set to 58 if need change to AUTO