Ray writes, “When your project needs a real-time clock (RTC), don’t you hate that the popular DS1307 costs several dollars? I recently came across Microchip’s MCP7940N, which is an inexpensive alternative to DS1307. On the hardware side it is pretty much a drop-in replacement (although Microchip recommends adding several extra elements). The software requires a few modifications. In this blog post I describe how to modify an existing Arduino DS1307RTC library to provide support for both chips.”
For more information as well as the code download link, visit Ray Hobby blog.
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