Recal clock

[homemade24]

I just added
bsf STATUS, RP0 ;Bank 1
call 3FFh ;Get the cal value
movwf OSCCAL ;Calibrate
bcf STATUS, RP0 ;Bank 0
had to to get the code working right
If I'm thinking right (that's scary) depending were you put this in the code
the clock could only be recal @ programming or could be recal everytime the chip is powered up. if so which is the standard way of doing it. and is it a problem if you recal every time the chip is powered up
thanks

 

[mvs sarma]

I just added
bsf STATUS, RP0 ;Bank 1
call 3FFh ;Get the cal value
movwf OSCCAL ;Calibrate
bcf STATUS, RP0 ;Bank 0
had to to get the code working right
If I'm thinking right (that's scary) depending were you put this in the code
the clock could only be recal @ programming or could be recal everytime the chip is powered up. if so which is the standard way of doing it. and is it a problem if you recal every time the chip is powered up
thanks

Please see this link
12F675 tutorial 3 : Adding a PIC Serial port.

 

[homemade24]

thanks
is that a YES or NO or did it mess something

 

[Nigel Goodwin]

It's absolutely critical that you don't erase the calibration value at 0x3FF - any decent programmer shouldn't allow you to do this, it should read and restore the value automatically.

The code for setting the calibration value is normally placed right at the beginning of the program to ensure it's set whenever the PIC boots up.

Bear in mind this isn't 'calibrating' the chip, it's simply using the value from when it was calibrated back in the factory.

 

[homemade24]

thanks Nigel
that clears it up and I guess calibrate was was not the correct term
it's more go get the factory setting and it need to do that with every boot up

 

[Nigel Goodwin]

thanks Nigel
that clears it up and I guess calibrate was was not the correct term
it's more go get the factory setting and it need to do that with every boot up

Yes, every time.