DS3231 RTC

ZS-042 schematic

There are at least two RTC modules containing the DS3231 available from China. Both can operate with the Raspberry Pi and one is designed especially for it.

One useful feature of the DS3231 other than keeping the time is its built-in temperature readout, however, initial tests suggest that this is inaccurate.

DS3231 for Pi

This device is as simple as it gets. There are two pull-up resistors for the I2C lines (4K3), a battery connected to the VBAT pin and a capacitor on the power rails.

This device plugs directly into the GPIO header.

I bought two of these devices and one was faulty. Fixing it simply involved applying pressure on each pin of the chip in turn with a hot iron, these devices may not be manufactured to a high standard.

DS3231 ZS-042

This module contains the RTC and an HK24C32 EEPROM. It tends to ship with a CR2032 battery and, as the per advice of many web sites, it's important to desolder the charge feature of the module (see schematic).

By default the EEPROM content is

./mcp24 1 0x57 -d
[0000] 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 |ABCDEFGHIJKLMNOP|
[0010] 51 52 53 54 55 56 57 58 59 5A FF FF FF FF FF FF |QRSTUVWXYZ......|
This website uses cookies. By using the website, you agree with storing cookies on your computer. Also you acknowledge that you have read and understand our Privacy Policy. If you do not agree leave the website.More information about cookies