; ======================================================================
; CS617 CHAPTER 03 - NATIVE FLOATING-POINT SUBTRACTION WRAPPER
;
; Donor: OM-52C C ROM, E99B..E9AA
; Contract: $10-$18 <- $10-$18 - $0-$8
; Dependency: shared low-ROM native FP subtraction service at &H0686
;
; Candidate status: not promoted until standalone validation passes.
; ======================================================================

BCD_SUB:
        PHSM    $29,8
        PHSM    $21,3
        CAL     &H0686
        PPSM    $19,3
        PPSM    $22,8
        RTN