On Mon, Nov 16, 2020 at 05:27 AM, Rafael Diniz wrote:
Did anybody managed to add a GPS to external referente the SI 5351?
Might be a round about way to do it. Depending on available pins.
In the time that the Nano processor is not doing much, let the Nano read the 1 PPS pulses from a GPS to get a counter value that would represent how far off the 16mhz CPU clock is.?
Then, once and a while, let the SI5351 generate a couple of mhz signal (extra unused SI5351 output) that is fed into an input of the Nano. Count that frequency, also.
Then calculate a correction factor for the SI5351 values needed to program it to the correct frequency.
Just a rough idea. Haven't kept track if any extra pins are still available on the Nano recently.
Tom, wb6b
