(Created page with "* arduino, on pin 3 a 1kHz clock signal ** the 1kHz clock signal is derived from a 10MHz OXCO via a PIC12F675 which divides it by 10k (see http://www.leapsecond.com/pic/src/pd...") |
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* when an interrupt comes in via pin 3, a uS timestamp is taken ('t0') | * when an interrupt comes in via pin 3, a uS timestamp is taken ('t0') | ||
* everytime the sign of the signal changes (via A0), then a timestamp is taken and the timestamp t0 is subtracted | * everytime the sign of the signal changes (via A0), then a timestamp is taken and the timestamp t0 is subtracted | ||
* also pin 8 is inverted (output pin) | |||
==== result ==== | ==== result ==== | ||
* it works somewhat but there's an enormous lapse | * it works somewhat but there's an enormous lapse | ||
[[File:50hztest001.png|640px]] | |||
* yellow is incoming 50Hz signal | |||
* blue is the toggle-pin (pin 8) | |||
Revision as of 15:07, 7 October 2022
- arduino, on pin 3 a 1kHz clock signal
- the 1kHz clock signal is derived from a 10MHz OXCO via a PIC12F675 which divides it by 10k (see http://www.leapsecond.com/pic/src/pd04.asm by Tom van Baak)
- the signal to measure is connected to pin A0 of the arduino
first attempt
- when an interrupt comes in via pin 3, a uS timestamp is taken ('t0')
- everytime the sign of the signal changes (via A0), then a timestamp is taken and the timestamp t0 is subtracted
- also pin 8 is inverted (output pin)
result
- it works somewhat but there's an enormous lapse
- yellow is incoming 50Hz signal
- blue is the toggle-pin (pin 8)