2PCS DS3231 ZS042 IIC Modulo Precisione Orologio in Tempo Reale Memoria Quare per Arduino

If the main power failure, the device can continue to provide accurate timing and temperature, performance is not affected. 4 clock chip: high-precision clock chip DS3231. 2 x DS3231 module. Wiring instructions (with Arduino uno r3 for example).

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