Osctune

[Acetronics2]

Would you please explain how you tested the osc freq? Could you share your test code?

I would like to learn more about this.

I usually base my projects around the following 3 PIC's, as they share the same basic pinout...
8pin - 12F683
14pin - 16F688
20pin - 16F690

I would like to learn how to set/test the osctune register. I would also like to know how to read a new chip to view the osctune register as set from the factory.

Thanks
Dwight

Hi, Dwight

I do not think you can tune OSCTUNE without a good time reference in one hand ...

What I do here is use my R/C set ... transmitter neutral is a precise 1500µs positive pulse ... and I also built a precise pulse meter ...

so, I just use the PULSOUT command to output a 1500µs pulse and trim OSCTUNE to get the good value on the meter.
Ok, I should write a small program and a board to make it automatically ( need 1 ref signal Pic, a thermostated enclosure ...etc,etc )... hoping I won't erase the EEPROM on the " live " programming !!!

Alain

PS: When leavin factory ... osctune is ... ZERO !!! ( see registers default values in the datasheet ... )