ld a, 1    ; Set flash page 1 in bank 1.
    out (6), a
    in a, (2)    ;get calc version
    rlca ;Roll bit 7 into carry.
    ld a, 41h ; Set ram page 1 in bank 2.
    jr nc, LowerModel
HigherModel:
    out (5),a
    ld a,81h
    out (7),a
    jr Return
LowerModel:
    out (6), a
    out (7),a
Return:
    ret