Maximum speed, all ports as I/O


At the moment I'm using the following with my PIC16F684:

__CONFIG(FCMDIS & IESODIS & BORDIS & UNPROTECT & MCLRDIS & PWRTEN &
WDTDIS & INTIO);

With this setting, the CPU clock is running at 4 MHz. I've heard tho
that it can run at 16 MHz. (I'm not using an external clock).

Does anyone know what I've to do to get it running at its top speed,
and with all pins set to I/O?

(I've looked over the data*** but it's too cryptic for me to make
any sense of it)


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