Routines

Address	Label	Description
AF6C	START	Cold start
AF7F	start_menu	Restart after a game
AF88	main	Set up and play
AFB7	player_dies	Start a life
AFBA	game_loop	Enter a room
AFBD	onscreen_loop	Walk the object table
AFC7	update_sprite_loop	Next object
AFD5	jump_to_upd_object	Dispatch on object type
AFDB	jump_to_tbl_entry	Jump through a table of addresses
AFE4	ret_from_tbl_jp	One object done
B000	end_of_frame	End of frame
B035	game_delay	Wait one unit
B038	delay_loop	Frame delay loop
B03F	no_delay	Redraw the whole screen on entering a room
B074	next_frame_or_die	Next frame, or lose a life
B088	reset_objs_wipe_flag	Clear every object's wipe flag
B090	clear_wipe_flag_loop	Clear one wipe flag
B2B6	play_audio_wait_key	Play the menu tune once per visit
B2BE	play_audio_until_keypress	Play a tune until a key is pressed
B2C5	keypress_tune_note	Play one note of a tune that a key can stop
B2CF	play_audio	Play a tune
B2D9	end_audio	End of a tune
B2DA	play_note	Play one note
B2F9	calc_duration	Multiply the waves by the length
B2FF	restore_tune_ptr	Restore the tune pointer
B300	note_wave	One wave
B304	note_first_half	First half-wave
B30F	note_second_half	Second half-wave
B31C	snd_delay	Rest
B327	rest_unit	One unit of rest
B328	rest_countdown	Rest countdown
B3E9	sound_movable_block	Sound: the movable block's blip
B403	sound_sparkle	Sound: sparkle
B40D	sparkle_blip	One blip of the sparkle
B419	sound_materialise	Sound: materialising
B423	materialise_sweep	One step of the materialising sweep
B42E	sound_thud	Sound: thud
B433	thud_blip	One blip of the thud
B441	sound_jump	Sound: jump
B443	jump_sweep	One step of the jump sweep
B451	sound_pitch_from_z	Sound: a note pitched by height
B454	sound_pitch_from_a	Sound: a note pitched by A
B45D	sound_pitch_from_x	Sound: a note pitched by X
B462	sound_pitch_from_y	Sound: a note pitched by Y
B467	sound_pitch_from_xyz	Sound: a note pitched by position
B472	sound_transform	Sound: changing between man and werewolf
B47D	transform_warble	One step of the warble
B489	sound_portcullis_crash	Sound: the portcullis lands
B495	crash_blip	One blip of the crash
B4A3	toggle_audio_hw_x16	Sound: a plain beep of 16 waves
B4A8	toggle_audio_hw_x24	Sound: a plain beep of 24 waves
B4AD	audio_guard_wizard	Sound: a guard's or the wizard's footstep
B4BB	sound_walk_step	Sound: Sabreman's footstep while walking
B4C1	sound_footstep	Sound: Sabreman's footstep
B4C6	footstep_pitch	Footstep pitch
B4D1	footstep_length	Footstep length
B4E6	toggle_audio_hw_xC	Sound: C waves at one pitch
B4ED	toggle_audio_hw	Sound: one wave
B4F2	speaker_on_wait	First half of the wave
B4F9	speaker_off_wait	Second half of the wave
B4FD	do_any_objs_intersect	Does this object overlap any other?
B510	overlap_test_obj	Test one object for overlap
B524	overlap_done	Overlap found, or none
B52E	overlap_next_obj	Next object
B538	is_object_not_ignored	Does this object take part in collisions?
B544	shuffle_objects_required	Rotate the list of objects the cauldron wants
B54C	rotate_wanted_once	Rotate once
B555	rotate_wanted_entry	Move one entry down
B566	upd_131_to_133	Handler: the finale sparks (types 131 to 133)
B593	p4_m4	Spark direction: dX -4, dY +4
B596	save_dX_dY	Store the spark's direction and pick a frame
B5A4	set_spark_frame	Set the spark's frame
B5A9	spark_tone_and_move	Leave the spark's height for the finale tone
B5AF	dec_dZ_wipe_and_draw	Move under gravity and flag for redrawing
B5B5	p4_p4	Spark direction: dX +4, dY +4
B5BA	m4_m4	Spark direction: dX -4, dY -4
B5BF	m4_p4	Spark direction: dX +4, dY -4
B5C4	spark_near_player	Is the spark near Sabreman?
B5CF	spark_check_y	Near on X; and on Y?
B5DE	spark_touch	Near on X; near on Y?
B5E3	spark_home_in	Fly at Sabreman
B5F7	read_port	Read one or more keyboard half-rows
B5FF	upd_182_183	Bouncing ball (types 182 and 183)
B626	bounce_ball_set_sense	Bouncing ball: set the chase direction and the bounce height
B63C	bounce_ball_on_landing	Bouncing ball: on landing, bounce
B64F	bounce_ball_pick_axis	Bouncing ball: choose X or Y and compare with the player
B65D	bounce_ball_y_sense	Bouncing ball: the patched jump for Y
B661	bounce_ball_set_dy	Bouncing ball: head along Y
B668	bounce_ball_animate	Bouncing ball: animate and draw
B66E	bounce_ball_x_axis	Bouncing ball: compare X with the player
B676	bounce_ball_x_sense	Bouncing ball: the patched jump for X
B67A	bounce_ball_set_dx	Bouncing ball: head along X
B683	upd_91	Dropping block (type 91)
B69F	drop_block_draw	Dropping block: draw
B6A2	upd_143	Collapsing block (type 143)
B6B1	upd_55	Shuttling block, north-south (type 55)
B6B9	upd_54	Shuttling block, east-west (type 54)
B6BF	shuttle_block	Shuttling block: the common part
B6DB	shuttle_block_target	Shuttling block: the target
B6DE	shuttle_block_step	Shuttling block: step towards the target
B6EF	shuttle_block_move	Shuttling block: move
B6F9	upd_144_to_149_152_to_157	Walking legs (types 144 to 149 and 152 to 157)
B716	legs_unmirrored	Walking legs: unmirrored
B71A	legs_animate_and_draw	Walking legs: animate and draw
B720	legs_face_minus_x	Walking legs: facing -X
B726	legs_moving_in_y	Walking legs: moving along Y
B730	legs_mirrored	Walking legs: mirrored
B736	legs_face_plus_y	Walking legs: facing +Y
B73C	upd_150_151	Guard walking east-west (types 150 and 151)
B749	guard_ew_move	Guard east-west: move and turn
B763	guard_ew_legs	Guard east-west: take the legs along
B76C	set_guard_wizard_sprite	Choose a guard's or the wizard's frame from its direction
B783	guard_unmirrored	Guard or wizard: unmirrored
B788	guard_face_minus_x	Guard or wizard: facing -X
B78E	guard_moving_in_y	Guard or wizard: moving along Y
B798	guard_mirrored	Guard or wizard: mirrored
B79D	guard_face_plus_y	Guard or wizard: facing +Y
B7A3	upd_22	Gargoyle (type 22)
B7A9	upd_63	Spiked ball (type 63)
B7CD	spiked_ball_drop	Spiked ball: fall
B7D9	draw_spiked_ball	Spiked ball: draw
B7DC	spiked_ball_landed	Spiked ball: landed
B7E7	upd_23	Spike (type 23)
B7ED	upd_86_87	Fire moving east-west (types 86 and 87)
B7FE	fire_ew_move	Fire east-west: move
B80F	upd_180_181	Fire moving north-south (types 180 and 181)
B820	fire_ns_move	Fire north-south: move
B82F	fire_turn_if_blocked	Fire: turn round if blocked
B83A	fire_flicker_and_draw	Fire: flicker and draw
B83F	upd_176_177	Fire standing still (types 176 and 177)
B856	set_deadly_wipe_and_draw_flags	Make an object deadly and mark it to be wiped and redrawn
B85C	set_both_deadly_flags	Make an object deadly both ways
B865	upd_178_179	Ball bouncing on the spot (types 178 and 179)
B876	ud_ball_rise_or_fall	Ball bouncing on the spot: rise or fall
B892	ud_ball_draw	Ball bouncing on the spot: draw
B894	ball_up	Ball bouncing on the spot: rise
B8A9	init_cauldron_bubbles	Start the cauldron bubbles
B8DA	upd_160_to_163	Cauldron bubbles (types 160 to 163)
B916	bubbles_draw	Cauldron bubbles: draw
B919	bubbles_turn_hostile	Cauldron bubbles: turn hostile
B923	upd_168_to_175	The object the wizard wants, shown in the bubbles (types 168 to 175)
B92C	upd_164_to_167	Chasing sparkles (types 164 to 167)
B942	chaser_speed_fast	Chasing sparkles: fast
B945	chaser_chase	Chasing sparkles: chase
B95E	upd_111	Make an object vanish (type 111)
B962	sound_wipe_and_draw	Play a sound, then wipe and draw
B965	move_towards_plyr	Point an object at the player
B973	towards_plyr_y	Point at the player: Y
B981	towards_plyr_set_dy	Point at the player: set dY
B985	toggle_next_prev_sprite	Flip between an object's two frames
B98C	next_graphic_no_mod_4	Step an object through four frames
B998	save_graphic_no	Store an object's type
B99C	upd_141	The cauldron (type 141)
B99F	upd_142	The cauldron's top (type 142)
B9A5	upd_30_31_158_159	Guard walking round the room, and the wizard (types 30, 31, 158 and 159)
B9CC	move_guard_wizard_NSEW	Choose a walking guard's next heading
B9E0	guard_W	Walking guard heading -X
B9EB	next_guard_dir	Walking guard: next heading
B9FB	guard_N	Walking guard heading +Y
BA08	guard_E	Walking guard heading +X
BA15	guard_S	Walking guard heading -Y
BA22	game_over	Game over
BA29	game_over_summary	The game-over summary screen
BA79	print_charms_and_show	Print the charms count and show the summary
BA87	await_restart	Wait, play the game-over tune, and start again
BA9B	wait_for_key_press	Wait a while or until a key is pressed
BA9E	wait_key_poll	One poll of the keyboard
BAAB	game_complete_msg	The quest is complete
BC10	calc_and_display_percent	Count the rooms visited and print the percentage of the quest
BC18	count_screens	Count the visited bits in one byte
BC1B	count_visited_bit	Test one bit of the visited map
BC1F	next_visited_bit	Next bit, next byte, then work out the percentage
BC38	scale_to_percent	Add 100/156 per point
BC61	print_percent_two_digits	Print a percentage under 100
BC66	print_days	Print the day count on the panel
BC7A	print_lives_gfx	Draw the lives icon on the panel
BCA3	print_lives	Print the number of lives
BCAE	print_BCD_number	Print BCD numbers in the standard font
BCB6	print_BCD_byte	Print both digits of one BCD byte
BCC0	print_BCD_lsd	Print the low digit of a BCD byte
BCCA	display_day	Draw the day label on the panel
BD0C	do_menu_selection	The control-method menu
BD15	clear_menu_flash	Clear the FLASH bit on every menu line, then draw the menu
BD23	menu_loop	The menu loop
BD3E	check_for_kempston_joystick	Key 2: Kempston joystick
BD46	check_for_cursor_joystick	Key 3: cursor joystick
BD4E	check_for_interface_ii	Key 4: Interface II joystick
BD54	check_for_directional_control	Store the method, then key 5: directional control
BD6C	check_for_start_game	Start the game?
BD85	clr_debounce	Key 5 released
BD89	flash_menu	Flash the selected menu lines
BE31	print_text_single_colour	Print a string in one given colour
BE45	print_text_std_font	Print a string with its colour byte, in the standard font
BE4C	print_text	Print a string with its colour byte
BE56	text_attr_addr	Find the attribute address for the string
BE5F	print_text_char	Print one character of a string
BE72	print_text_last	Print the last character of a string
BE7F	print_8x8	Print one 8x8 character into the buffer
BE91	print_8x8_row	Copy one row of the glyph
BEA3	toggle_selected	Set the FLASH bit on one of a list of colours
BEA6	flash_this_one	Flash this colour
BEAA	flash_next_one	Count down to the chosen colour
BEAD	unflash_this_one	Do not flash this colour
BEAF	flash_list_step	Next colour in the list
BEB3	display_menu	Draw the menu
BEBF	display_text_list	Print a list of strings
BEE4	multiple_print_sprite	Print a sprite several times in a line
BEFE	upd_120_to_126	Player appearing, frames 120 to 126
BF11	upd_127	Player appearing, last frame
BF21	init_death_sparkles	Start the sparkle an object vanishes in
BF2B	upd_112_to_118_184	Sparkle, frames 112 to 118 (and type 184)
BF31	sparkle_sound_and_draw	Sparkle sound and redraw
BF37	upd_185_187	Vanish and leave the special-object table
BF3F	upd_119	Sparkle, last frame: vanish
BF45	display_objects_carried	Redraw the carried objects if they changed
BF4E	display_objects	Draw the three carried objects on the panel
BF59	display_object	Draw one carried object
BF91	show_carried_slot	Show one carried object and colour it
BFFB	chk_pickup_drop	Is the pick-up/drop control pressed?
C00B	test_pickup_bit	Test the pick-up bit
C00E	handle_pickup_drop	Pick up or drop an object
C041	start_pickup_drop	Look for a charm to pick up
C06F	try_pickup_loop	Try each special-object record
C08C	find_free_record	Nothing to pick up: find a free record to drop into
C093	find_free_record_loop	Is this record free?
C09D	done_pickup_drop	Pick-up or drop done
C0A9	wait_pickup_release	Wait for the pick-up key to be released
C0B2	room_to_drop	Drop the oldest charm carried
C0DD	place_under_player	Put the charm under the player
C106	drop_object	Fill in a dropped charm's record
C12B	adjust_carried	Shift the carried slots along
C141	pickup_object	Pick up a charm
C172	can_pickup_spec_obj	Can this special object be picked up?
C17A	is_on_or_near_obj	Is the player on or next to this object?
C19F	near_obj_done	Result of the touch test
C1A1	is_obj_moving	Is the object moving?
C1AB	upd_103	Special object $67: the extra life
C1EE	extra_life_fall	Fall and settle like any other object
C1F1	upd_104_to_110	A charm on its way into the cauldron, types $68 to $6E
C202	steer_to_centre_y	Steer towards the centre in y
C213	check_over_centre	Over the centre yet?
C222	rise_over_cauldron	Rise to a height of $98
C22C	store_rise_speed	Set the vertical speed
C22F	move_charm_to_cauldron	Move it
C232	click_wipe_and_draw	Click and redraw
C238	centre_of_room	Over the centre: fall into the cauldron
C245	add_obj_to_cauldron	A charm lands in the cauldron
C265	cauldron_consume	Use the charm up
C274	ret_next_obj_required	Which charm the wizard wants next
C28B	upd_96_to_102	Special objects $60 to $66: a charm lying in a room
C29B	settle_charm	Stop the charm and redraw it
C2A5	cycle_colours_with_sound	Cycle the screen's colours with a sound
C2A7	cycle_colours_pass	One pass over the attributes
C2AD	cycle_attribute_mem	Step one cell's ink
C2C3	cycle_colours_pause	Pause between passes
C2CB	no_update	Handler that does nothing
C2CC	prepare_final_animation	Start the final animation
C2DC	final_clear_loop	Erase the next of records 3 to 13
C2EE	blocks_to_rising	Turn a stone block into a rising block
C2F9	final_next_record	Next record in the stone-block scan
C306	chk_and_init_transform	Start the transformation if one is due
C337	upd_92_to_95	The transformation in progress (types 92 to 95)
C349	transform_step	One step of the transformation
C357	rand_legs_sprite	Show a random transformation sprite
C369	set_transform_sprite	Set the transformation sprite
C377	finish_transform	End the transformation
C394	transform_done_draw	Draw the finished player
C397	print_sun_moon	Move the sun or moon on
C3A4	display_sun_moon_frame	Place the sun or moon, and redraw its window
C3C3	display_frame	Draw the sun and moon window
C3FF	toggle_day_night	Swap the sun and moon
C419	inc_days	A new day
C432	blit_2x8	Copy a 16 by 8 pixel patch from the buffer to the screen
C46D	init_sun	Start the first day
C47E	init_special_objects	Shuffle the special objects
C489	init_obj_loop	Set up one special-object entry
C4AA	upd_62	The block type called moveable (type 62)
C4B6	upd_85	A chest (type 85)
C4C3	upd_84	A table (type 84)
C4C6	dec_dZ_upd_XYZ_wipe_if_moving	Move under gravity, and redraw if moved
C4D3	upd_128_to_130	Drawing offset X -8, Y -2 (types 128 to 130)
C4D8	adj_m4_m12	Drawing offset X -12, Y -4
C4DD	adj_m6_m12	Drawing offset X -12, Y -6
C4E0	jp_set_pixel_adj	Jump to set the drawing offset
C4E3	upd_6_7	Drawing offset X -16, Y -8 (types 6 and 7)
C4E8	upd_10	Drawing offset X -20, Y -1 (type 10)
C4ED	upd_11	Drawing offset X -12, Y -2 (type 11)
C4F2	upd_12_to_15	Drawing offset X -8, Y -4 (types 12 to 15)
C4F7	adj_m8_m12	Drawing offset X -12, Y -8
C4FC	adj_m7_m12	Drawing offset X -12, Y -7
C501	adj_m12_m12	Drawing offset X -12, Y -12
C506	upd_88_to_90	Drawing offset X -16, Y -12 (types 88 to 90)
C50B	adj_p7_m12	Drawing offset X -12, Y +7
C510	adj_p3_m12	Drawing offset X -12, Y +3
C515	fill_window	Fill a rectangle of bytes
C518	fill_window_row	Fill one row
C51A	fill_window_byte	Fill one byte
C525	find_special_objs_here	Bring in the special objects for a new room
C530	find_spec_obj_loop	Check one special-object entry
C572	next_spec_obj_slot	Next special-object entry
C583	clear_spare_spec_records	Clear the unused special-object records
C591	update_special_objs	Remember where the special objects were left
C595	save_spec_obj_loop	Write back one special object
C5B7	save_spec_obj_next	Next special-object record
C5C8	upd_80_to_83	A ghost (types 80 to 83)
C5DD	ghost_new_direction	Give a ghost a new direction
C5FD	ghost_animate	Animate a ghost
C603	calc_ghost_sprite	Choose a ghost's sprite from its direction
C60C	ghost_abs_dy	The size of dy
C616	ghost_pick_view	Mostly along x, or mostly along y?
C624	set_ghost_hflip	Mirror the ghost
C629	ghost_x_negative	Moving towards -x
C62F	ghost_mostly_y	Moving mostly along y
C63A	clr_ghost_hflip	Don't mirror the ghost
C63F	ghost_y_negative	Moving towards -y
C645	get_delta_from_tbl	Look up a speed
C65E	upd_8	A portcullis at rest (type 8)
C685	init_portcullis_down	Start a portcullis falling
C691	count_moving_portcullis	Count the moving portcullis
C692	set_wipe_and_draw_flags	Mark an object to be wiped and redrawn
C69D	set_wipe_and_draw_IY	Mark the object at IY to be wiped and redrawn
C6AD	init_portcullis_up	Start a portcullis rising
C6BD	upd_9	A moving portcullis (type 9)
C6E0	stop_portcullis	Stop a portcullis
C6EA	move_portcullis_up	Raise a portcullis
C700	dec_dZ_and_update_XYZ	Apply gravity and move
C706	add_dXYZ	Move by the velocity
C722	upd_3_5	The second pillar of an arch (types 3 and 5)
C72B	set_pixel_adj	Set the drawing offset
C732	adj_3_5_hflip	The second pillar, mirrored
C737	adj_m3_p1	The first pillar of a tree arch, facing east or west
C73C	upd_2_4	The first pillar of an arch (types 2 and 4)
C74C	arch_ew_doorway	The middle of an east or west arch
C760	arch_check_doorway	Check the player against the doorway
C76C	adj_2_4_hflip	The first pillar, mirrored: a north or south arch
C785	arch_nudge_to_centre	Nudge the player towards the middle of an arch
C791	arch_nudge_loop	Nudge one record
C7B1	adj_ew	Nudge along y, for an east or west arch
C7BF	nudge_y_store	Store the y nudge
C7C4	adj_ns	Nudge along x, for a north or south arch
C7D2	nudge_x_store	Store the x nudge
C7D5	arch_nudge_done	Nudge done
C7D6	arch_nudge_next	Next record to nudge
C7DB	chk_plyr_spec_near_arch	Is the player in the doorway?
C7E4	near_arch_loop	Check one record against the doorway
C7F9	near_arch_next	Next record for the doorway check
C7FE	is_near_to	Is an object near a point?
C808	near_check_y	Within the limit along x?
C814	near_check_z	Within the limit along y?
C820	near_z_compare	Within 4 along z?
C823	upd_16_to_21_24_to_29	The knight's legs (types 16 to 21 and 24 to 29)
C828	upd_48_to_53_56_to_61	The werewolf's legs (types 48 to 53 and 56 to 61)
C82B	upd_player_bottom	Update the player's legs
C83E	player_controls	Read the controls and act on them
C855	player_move_and_draw	Move the player and count down the room-entry walk
C86A	player_redraw	Have the player redrawn
C86D	plyr_OOB	In a doorway: allow no rising
C87A	chk_plyr_OOB	Is the player inside the room's walls?
C891	oob_test_x	Test X, then work out the Y distance
C89D	oob_test_y	Test Y
C89F	handle_left_right	Turn the player
C8BE	directional_pick	Directional control: right, down or left
C8CD	chk_facing_N	Directional control: face N
C8D2	chk_facing_ne_result	Directional control: walk, or turn towards N or E
C8D5	turn_by_parity	Directional control: turn left or right
C8D9	chk_facing_E	Directional control: face E
C8E0	chk_facing_S	Directional control: face S
C8E5	chk_facing_sw_result	Directional control: walk, or turn towards S or W
C8E9	chk_facing_W	Directional control: face W
C8EF	flag_forward	Directional control: walk
C8F2	left_right_rotational	Rotational control: turn a quarter
C8FD	rotational_turn	Rotational control: start a turn
C915	start_turn_delay	Rotational control: set the pause and choose the direction
C91F	left_right_calc_sprite	Turn the player one quarter
C927	turn_toggle_view	Turn: change between back and front view
C92F	turn_toggle_mirror	Turn: mirror the sprite, and turn the top half to match
C940	turn_right	Turn right
C948	handle_jump	Start a jump
C969	handle_forward	Step the legs
C97A	walk_step_sound	Footstep, then the next leg frame
C97F	animate_human_legs	Next frame of a walk cycle
C98B	store_leg_frame	Store the new leg frame
C994	legs_to_rest	Bring the legs to rest
C9A1	move_player	Move the player
C9AB	move_player_xy	Is the player moving forward?
C9BC	move_player_walk	Take a step forward
C9C1	apply_gravity	Gravity
C9CC	gravity_extra	Gravity's second unit
C9CD	move_player_apply	Resolve and apply the move
C9F3	clear_dX_dY	Clear dX and dY
C9FB	calc_plyr_dXY	Add a step in the facing direction
CA17	dispatch_on_facing	Jump by the object's facing
CA1E	get_sprite_dir	Which way does the object face?
CA3A	move_plyr_W	Step west
CA3F	store_plyr_dX	Store dX
CA43	move_plyr_E	Step east
CA4A	move_plyr_N	Step north
CA4F	store_plyr_dY	Store dY
CA53	move_plyr_S	Step south
CA5A	adj_dZ_for_out_of_bounds	Shorten dZ at the floor
CA5E	clip_dZ_to_floor	Shorten dZ at the floor: the loop
CA70	handle_exit_screen	Has the player walked out of the room?
CA89	shorten_delta	Shorten a movement by one unit
CA90	shorten_delta_dec	Shorten a movement: subtract one
CA9A	screen_west	Leave by the west wall?
CAB3	screen_e_w	Keep an east-west move within the row
CABA	exit_screen	Go into the next room
CAF3	screen_east	Leave by the east wall?
CB0E	screen_north	Leave by the north wall?
CB29	screen_south	Leave by the south wall?
CB45	adj_for_out_of_bounds	Cut a move short against the room and the other objects
CB6A	dZ_ok	Cut a move short: X
CB7B	dX_done	Cut a move short: Y
CB8C	store_clipped_move	Store the move as cut
CB9A	adj_dX_for_obj_intersect	Shorten dX against the other objects
CBA0	dX_obj_loop	Shorten dX: is this object in line?
CBAF	dX_obj_hit_test	Shorten dX: does the move hit it?
CBD9	dX_obj_shorten	Shorten dX by one and try the same object again
CBE1	dX_obj_next	Shorten dX: the next object
CBE9	adj_dY_for_obj_intersect	Shorten dY against the other objects
CBEF	dY_obj_loop	Shorten dY: is this object in line?
CBFE	dY_obj_hit_test	Shorten dY: does the move hit it?
CC28	dY_obj_shorten	Shorten dY by one and try the same object again
CC30	dY_obj_next	Shorten dY: the next object
CC38	adj_dZ_for_obj_intersect	Shorten dZ against the other objects
CC3E	dZ_obj_loop	Shorten dZ: is this object above or below?
CC4D	dZ_obj_hit_test	Shorten dZ: does the move hit it?
CC81	dZ_ride_dY	Shorten dZ: ride with the obstacle's dY
CC8D	dZ_obj_shorten	Shorten dZ by one and try the same object again
CC95	dZ_obj_next	Shorten dZ: the next object
CC9D	do_objs_intersect_on_x	Do two objects overlap in X?
CCB0	intersect_x_result	Overlap in X: compare
CCB2	do_objs_intersect_on_y	Do two objects overlap in Y?
CCC5	intersect_y_result	Overlap in Y: compare
CCC7	do_objs_intersect_on_z	Do two objects overlap in Z?
CCD6	intersect_z_result	Overlap in Z: compare
CCD8	intersect_z_above	Overlap in Z: the other object is lower
CCDD	adj_dX_for_out_of_bounds	Shorten dX at the walls
CCEC	clip_dX_to_walls	Shorten dX at the walls: distance from the centre
CCF6	clip_dX_test	Shorten dX at the walls: test and shorten
CD07	dX_ok	Shorten dX at the walls: done
CD08	adj_dY_for_out_of_bounds	Shorten dY at the walls
CD17	clip_dY_to_walls	Shorten dY at the walls: distance from the centre
CD21	clip_dY_test	Shorten dY at the walls: test and shorten
CD32	dY_ok	Shorten dY at the walls: done
CD33	calc_2d_info	Work out an object's screen rectangle
CD43	store_2d_size	Store the sprite's width and height
CD4D	set_draw_objs_overlapped	Mark every object the moving object's old or new rectangle touches
CD6C	union_right_edge	Union rectangle: right-hand edge
CD7A	union_width_bottom	Union rectangle: width, and the lower edge
CD87	union_top_edge	Union rectangle: the upper edge
CD99	union_height	Union rectangle: the height
CD9B	test_overlap_obj	Test one object against the union rectangle
CDB3	overlap_x_decided	Horizontal overlap decided
CDBC	overlap_y_decided	Vertical overlap decided: mark the object
CDC2	next_overlap_obj	Next object for the overlap test
CDCC	obj_starts_left	Object starts to the left of the union
CDD3	obj_starts_below	Object starts below the union
CDDA	upd_32_to_47	Object types 32 to 47: the knight's head
CDDF	upd_64_to_79	Object types 64 to 79: the werewolf's head
CDE2	upd_player_top	Update the player's head
CDEF	head_follows_legs	The head follows the legs
CE14	choose_head_sprite	Choose the head sprite
CE22	set_top_sprite	Set the head's sprite
CE27	head_on_shoulders	Put the head on the shoulders
CE33	head_frame_six	Head frame 6
CE3A	hold_head_frame	Hold the chosen head frame
CE40	head_frame_seven	Head frame 7
CE49	save_2d_info	Remember an object's screen rectangle
CE62	list_objects_to_draw	List the objects to be drawn this frame
CE72	list_test_obj	Test one object for the draw list
CE80	list_next_obj	Next object for the draw list
CEBB	calc_display_order_and_render	Draw the listed objects, back to front
CEC3	process_remaining_objs	Start a pass: find the first object not yet drawn
CEC6	skip_drawn_entries	Skip entries already drawn
CEDB	compare_next_obj	Compare the candidate with the next undrawn object
CF15	z_code_overlap	Z code: the boxes overlap in height
CF16	compare_along_y	Compare the boxes along Y
CF39	add_y_code	Add the Y code
CF3C	compare_along_x	Compare the boxes along X
CF5F	add_x_code	Add the X code
CF62	act_on_comparison	Act on the comparison
CF9F	order_unconstrained	Pair with no order between them
CFA2	candidate_already_first	Candidate is behind the other object
CFA5	iy_goes_first	The other object must be drawn first
CFAD	search_chain	Search the candidate chain
CFB8	iy_becomes_candidate	IY becomes the candidate
CFCE	break_order_cycle	Break a cycle in the order
CFD1	find_iy_entry	Find IY's entry and draw it
CFE1	objs_coincide	Two boxes occupy the same space
CFF0	check_iy_collectable	Is the other one a collectable?
CFFD	coincide_done	Continue after two boxes intersect
D000	render_obj_no1	Draw the candidate
D003	render_obj	Draw an object and start the next pass
D015	render_done	All listed objects drawn
D022	check_user_input	Read the controls
D03E	interface_ii	Interface II joysticks
D046	reverse_if2_bits	Reverse the 1 to 5 bits
D05C	if2_up	Interface II up
D062	if2_down	Interface II down
D068	if2_right	Interface II right
D06E	if2_left	Interface II left
D074	if2_done	Interface II done
D077	kempston	Kempston joystick
D081	kempston_left	Kempston left
D087	kempston_down	Kempston down
D08D	kempston_up	Kempston up
D093	kempston_fire	Kempston fire
D099	kempston_done	Kempston done
D09C	cursor	Cursor keys
D0A9	cursor_second_row	Cursor keys: the 6 to 0 half-row
D0B4	cursor_up	Cursor up
D0BA	cursor_right	Cursor right
D0C0	cursor_down	Cursor down
D0C8	keyboard	Keyboard
D0E4	keyboard_m	Keyboard: M
D0EA	keyboard_n	Keyboard: N
D0F0	keyboard_b	Keyboard: B
D0F6	keyboard_forward	Keyboard: walk forward
D0FF	keyboard_jump	Keyboard: jump
D108	keyboard_pickup	Keyboard: pick up and drop
D111	finished_input	Finish reading the controls
D125	store_input	Store the control bits
D12A	lose_life	Start a life
D1B1	init_start_location	Set up the player for a new game
D1E6	build_screen_objects	Build the room the player is in
D1EF	build_room	Fill the object table for the new room
D219	flag_room_visited	Mark the player's room as visited
D237	transfer_sprite	Copy a sprite's four bytes into the drawing record
D24C	transfer_sprite_and_print	Copy a sprite's four bytes and draw it
D255	display_panel	Draw the scroll-work at the foot of the screen
D296	print_border	Draw the border round the play area
D2EF	colour_panel	Colour the sun and moon window's frame
D30D	colour_sun_moon	Colour the sun or the moon
D317	fill_sun_moon_colour	Fill the window's colour
D320	adjust_plyr_xyz_for_room_size	Put the player in the doorway he came through
D33F	enter_arch_s	Enter through the south arch
D34A	adjust_plyr_y	Set the player's Y
D34D	plyr_redraw_copy_xy	Redraw the player and line the head up with the legs
D362	enter_arch_n	Enter through the north arch
D36F	enter_arch_w	Enter through the west arch
D37A	adjust_plyr_x	Set the player's X
D37F	enter_arch_e	Enter through the east arch
D38C	adjust_plyr_Z_for_arch	Stand the player on the floor of the arch
D395	check_next_arch	Look at the next arch
D3A9	adj_plyr_Z	Take the arch's Z
D3B5	get_ptr_object	Object index to record address
D3C6	retrieve_screen	Build the objects of the room the player has entered
D3CF	find_screen	Find the room's record
D3E2	zero_end_of_graphic_objs_tbl	Clear the object records from DE to the end of the table
D3F0	found_screen	Take the room's colour and size from its record
D41E	next_bg_obj	Next background in the room's list
D432	next_bg_obj_sprite	Copy one background template into an object record
D44C	find_fg_objs	Start on the room's foreground objects
D452	next_fg_obj	Read a foreground group: its type, count and first location
D46B	next_fg_obj_in_count	Place one more of the same type
D46C	next_fg_obj_sprite	Build one object record from a foreground template and a location
D4CD	zero_fg_obj_tail	Clear the rest of a foreground record, then carry on
D4EA	end_of_fg_objs	The room record is used up
D4F2	add_HL_A	Add A to HL
D4F9	HL_equals_DE_x_A	HL = DE * A
D4FF	mult_step	One bit of the multiply
D504	mult_next_bit	Next bit of the multiply
D508	zero_DE	Clear B bytes at DE
D509	fill_DE	Fill B bytes at DE with A
D50E	handle_pause	Pause if SPACE is pressed
D519	debounce_space_press	Wait for SPACE to be let go, then sound
D525	wait_for_space	Paused: wait for SPACE again
D52E	debounce_space_release	Wait for SPACE to be let go, sound, and carry on
D53A	clr_mem	Clear BC bytes at HL
D53C	clr_byte	Fill BC bytes at HL with E
D544	clr_bitmap_memory	Clear the display bitmap
D54C	clr_attribute_memory	Set every attribute to bright yellow on black
D556	fill_attr	Set every attribute to A
D55F	clear_scrn	Clear the screen and make the border black
D567	clear_scrn_buffer	Clear the screen buffer
D56F	update_screen	Copy the whole buffer to the display, clearing it as it goes
D578	update_screen_row	One row of the whole-screen copy
D57B	update_screen_byte	Copy and clear a row, then step to the display line above
D59A	update_screen_next_row	Next row of the whole-screen copy
D59F	render_dynamic_objects	Redraw what changed and copy it to the display
D5B2	wipe_next_object	Wipe the next object that moved
D5DB	wipe_right_edge	Find the right edge of the area to wipe
D5F6	wipe_width	The width of the area, and its bottom edge
D60B	wipe_top_edge	Find the top edge of the area to wipe
D61C	wipe_height	The height of the area, cut off at the top of the screen
D62C	wipe_rect	Wipe the area in the buffer and remember it
D649	wipe_left_is_new	The new x is the further left
D64E	wipe_bottom_is_new	The new y is the lower
D653	draw_and_copy_rects	Draw the objects, then copy the wiped areas to the display
D666	copy_next_rect	Copy the next wiped area to the display
D679	copy_rects_done	All copied
D67C	blit_to_screen	Copy a rectangle of the buffer to the display
D69A	blit_next_row	Next row of the rectangle
D69E	build_lookup_tbls	Build the lookup tables
D6A0	shift_tbl_value	Start on one byte value
D6A7	shift_tbl_entry	Store the value shifted one place further
D6BB	reverse_tbl_value	Start reversing one byte value
D6BE	reverse_tbl_bit	Move one bit across
D6C9	calc_pixel_XY	Project an object's position onto the screen
D6EF	flip_sprite	Find an object's sprite and make it face the right way
D704	calc_pixel_XY_and_render	Draw one object from the render list
D710	project_and_draw	Project the object and draw it if it is on the screen
D718	print_sprite	Draw an object's sprite into the buffer, through its mask
D73C	patch_sprite_rows	Patch the row loop for this width, and cut the height to the screen
D75A	draw_sprite_rows	Draw the rows
D76F	sprite_aligned	The byte-aligned case, and the start of its unrolled run
D790	sprite_aligned_tail	The last three units of an aligned row
D7AA	sprite_row	Start a row
D7AC	sprite_row_jump	Jump into the row, then the shifted run
D7FF	sprite_row_end	Step to the row above
D800	sprite_next_row	Move BC up a row, and loop
D811	calc_vidbuf_addr	Buffer address of a pixel position
D826	calc_vram_addr	Display address of a pixel position
D848	calc_attrib_addr	Attribute address of a pixel position
D865	vflip_sprite_data	Turn a sprite's stored data to face the way its object wants
D88C	vflip_row_pair	Swap the next pair of rows
D88D	vflip_sprite_line_pair	Swap two rows byte by byte, working backwards
D8A2	hflip_sprite_data	Mirror the sprite if its object wants it the other way round
D8BF	hflip_read_row	Push a row's pairs, each byte reversed
D8CD	hflip_write_row	Write the row back in the reverse order
D8DC	flip_done	Return with DE on the header