CODE PICK
    HL POPqq,
    ( x2 )
    L SLAr, H RLr,
    SP ADDHLss,
    C (HL) LDrr,
    HL INCss,
    B (HL) LDrr,
    ( check PS range before returning )
    EXDEHL,
    HL PS_ADDR LDddnn,
    DE SUBHLss,
    CC lblofl @ JPccnn,    ( abortUnderflow-B298 )
    BC PUSHqq,
;CODE