Boot:
	xor a	; Kill USB interrupts from the start to avoid problems

	out (57h), a

	out (5Bh), a
Shutdown:
	di
	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, _
	out (5),a
	ld a,81h
	out (7),a
	jr ++_
_	out (6), a
	out (7),a
	ld sp, 0FFFFh
_	call Sleep