pic16LF819 not working with 3.3V

[jjohannson]

Does anyone know is there is a register value I have to set to get my pic16LF819 to work with 3.3V. It works fine with 5V.

[Ron Marcus]

What frequency are you at...And, have you tried HS oscillator setting if you are using a crystal/resonator? What about trying the internal oscillator to see if that works?

[jjohannson]

I'm using a 4MHz external crystal and have XT_OSC set. This circuit works fine with an pic16F818 and pic16F84A but not with PIC16LF819 and like I mentioned earlier if I use 5 Volts as power supply the chip runs.

[jjohannson]

I found in the sheets that if VDD goes below 4V a reset on brown out can occur and keep the chip from firing up.
I have a line of code that reads

@ DEVICE XT_OSC, MCLR_OFF

I think this assembly statelment sets or resets configuration bits. I do not know the syntax for turning off or on other configuration bits. Does anyone know how to reset BOR or where this information is.

[Archangel]

I think what Ron was trying to say is: The oscillator gets more power when HS is set instead of XT. I read that somewhere.

[jjohannson]

I tried the HS setting and it still does not work. I think it has something to do with the Reset on Brown Out and I don't know how to deactivate the BOR