XT_OSC might be better for a 4MHz crystal, and BODEN_OFF would help when operating
below the Brown-Out Reset Voltage, but I think the primary show-stopper is trying to run
the non LF version 877A below the minimum operating voltage.

The LF part can operate on 2 to 5.5V. The non LF needs 4 to 5.5V. Check the Electrical
Specifications section in your datasheet.

Brown-Out reset on the non LF part can be anywhere from 3.65V, 4.0V or 4.35V.