October 20, at am Hi Hanish, Your question is a good one, and has a lot of subtleties that make it hard to answer without knowing your exact situation. That said, I used two methods, one fast and one slow. In the intervening time it can be turned off, if you wish. The DS must have continuous power and be uninterrupted at all times through the measurement. See here for details.
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October 20, at am Hi Hanish, Your question is a good one, and has a lot of subtleties that make it hard to answer without knowing your exact situation. That said, I used two methods, one fast and one slow. In the intervening time it can be turned off, if you wish. The DS must have continuous power and be uninterrupted at all times through the measurement. See here for details. Write that down. You just need to write down one line from that output, the rest is just periodic updates.
Next, ensure that your system is not automatically resetting the DS — typically a Linux system will do this automatically every 11 minutes. I then subtract the set offset from the read offset that is, 4 seconds — 0. This means that over the course of 30 days, the clock drifted by 3. I then divide that value by the number of seconds the clock was running 3.
Multiply that by one million 0. In my example, this works out to be 1. Not bad. This method is very slow, but has the advantage of not requiring any manual effort other than setting and reading the clock.
Letting it run quietly on a shelf for a month or two is pretty easy. The fast method requires a precise time standard that outputs one pulse per second e.
Connect the PPS to one channel and set the oscilloscope to trigger on the PPS signal so it will update once per second.
They are quite different. Start a timer or stopwatch when a rising edge of the 32kHz output reaches a convenient point e. Take the reciprocal of that time in seconds, then divide that by Multiply that by one million to get the results in ppm: 0. I wrote a shell script that will let me set the aging offset and send the manual conversion command so I can quickly tune the aging offset while looking at the oscilloscope I adjust until the drift rate is minimized.
Just set or keep the aging offset to zero and let the clock do its thing automatically. I hope this helps a bit. Good luck!
DS3232SN# Maxim Integrated Products, DS3232SN# Datasheet
Additionally, the DS incorporates a battery input and maintains accu- rate timekeeping when main power to the device is inter- rupted. The integration of the crystal resonator enhances the long-term accuracy of the device as well as reduces the piece-part count in a manufacturing line. The DS is available in commercial and industrial temperature ranges, and is offered in an industry-standard pin, mil SO package. The RTC maintains seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year.
DS3232 Maxim, DS3232 Datasheet