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Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@asez73
Yes, my Espruino 1v4 did not kept accurately time with interpreter 1v72 in spite of its external 32 khz...
Now I need to look back at my sources to get it was drifting. Actually, i used egyptian fractions to correct the time.
A user access to calibrate would be a good idea. Apparently, there is the same example for stm32l1 on another github repository.
So far 7800 ppm is terribly better than 100 000 ppm, and it should ease a lot of log.
As far as I understand there are some eeprom available to save calibration results.
Also the smooth calibration is designed to handle temperature drift, which I guess should become usefull once we get down to autocalibration predicted results.
The best of all would be to use the 1 hz pulse from a gps which is possible with almost all gps chips. The ublox one's are capable of doing it on their tx pin. However you have to disable all nmea sentences on rus1. At least there also a special pin, but it is not always outputed depending of your gps board manufacturer.