Hello. (In the cheap Chinese modules) DS1307 are not accurate. In a DIY clock for my own personal use (bedside clock ;) ) I estimated the drift and corrected it in software, daily. That can be done since it runs 24/7. I had also found an algorithm that computes the total drift from the set timestamp, when the delta was presumably zero, storing values in EEPROM.
DS3231 seems to be much more stable and has some calibration/drift routines too (I must read the datasheet). The little extra cost is certainly worth. One word of caution. All DSx RTC modules I got from China were configured to charge the backup button cell (LIR2032). If you usually install CR2032's don't forget to remove the diode or resistor coming from Vcc. If you design your own circuits, that's a non-issue. If you need a vintage look, I have a couple of 2.097152 MHz XTALs in HC33/U case laying around (that's 2^21). Paolo -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/CABj2Vaai9_mA1zTgvyoOH6J_tgEeEqnx%3DFHHms5ntN4qz2onGA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
