Accumulating fraction bits (fractions of 16; bits 4-7 used while bits 0-3 are always zero; #%XXXX0000) for fixed point player X position (not to be confused with $7E007A). This is used mainly for player's X speed position movement to enable increments for less-than a pixel.
[remove previous version please, $7E13DC and $7E13DA are fixed point POSITIONS, not speed, they are meant so if they go past 15/16 (#%11110000), would move the player a pixel when $7E007B/$7E007D is a nonzero value]
Accumulating fraction bits for fixed point player Y position. Same format as $7E13DA but Y position instead of X.