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PIC 18 Series - HS+PLL Enabled Clock Mode

Started by John Lucas October 8, 2004
Hi

I am using a PIC18F452 with an external 8MHz crystal. I am trying to
enable the HS+PLL Enabled mode, the device programs okay, and when
read back, the configuration values are correct, however, in use, the
device is still running at 8MHz. I am using MPLAB 6.62 with an ICDII.
Can anyone suggest a reason why the PLL may not be working.

Thanks

John Lucas
> I am using a PIC18F452 with an external 8MHz crystal. I am trying to > enable the HS+PLL Enabled mode, the device programs okay, and when > read back, the configuration values are correct, however, in use, the > device is still running at 8MHz. I am using MPLAB 6.62 with an ICDII. > Can anyone suggest a reason why the PLL may not be working. > > Thanks > > John Lucas
In the ICD2 help file under 18Fxxxx limitations look for the note on Programmer Limitations for programming the PLL. I think you have to remove power after programming PLL, then re-apply for the change to take affect. Assuming you have it set under Configure >>Configuration Bits... HS-PLL Enabled, it should work. -- -Bruce http://www.rentron.com
Cheers mate. That works a treat

John