External osc defines

[Bruce]

Try the attached .hex file with your oscillator connected to RA7. This is your code compiled
with EC oscillator settings I posted previously.

If it doesn't work I would guess you have a bad PIC, oscillator, or both. Or your programmer
is not using the config options embedded in the .HEX file.

This @config_EXTCLK_OSC is not valid, so it does nothing to set EC mode. Whatever config
options you're getting programmed into the PIC are the defaults in 16F628a.inc. Normally osc
is set to XT in the defaults. In this mode, OSC2 provides the drive for an external crystal circuit
like the one shown in first diagram on the link you posted.