Chase H.Q.

main

Address	Description
4000	Screen memory
5B00	The game has loaded
5BD7	Padding bytes
5C00	[Stage 1] Horizon graphic
5CF0	[Stage 1] Per-stage data
5D0C	[Stage 1] Table of addresses of LODs
5D1A	[Stage 1] Per-stage difficulty settings
5D1D	[Stage 1] Per-stage setup data
5D2B	[Stage 1] Per-stage attract mode data
5D39	[Stage 1] Nancy's perp description
5DED	[Stage 1] Arrest messages
5E40	[Stage 1] Graphics definitions
5EC4	[Stage 1] Map: Start stretch
5FD2	[Stage 1] Map: Left fork (wrong way)
6088	[Stage 1] Map: Right fork (correct way - dirt track)
6173	[Stage 1] Map: Tunnel section
61D4	[Stage 1] Map: Loop section
638A	[Stage 1] Ralph the Idaho Slasher's mugshot
643E	[Stage 1] LODs
7636	[Stage 1] Spare space
76F0	[Graphics] Turbo icons
7798	[Pre-game] Messages
77D8	[Pre-game] Drawing commands for the pre-game screen
7A0F	[Graphics] Smoke and fire graphics
7BE9	[Graphics] Faces
7E05	[Graphics] Street lamps etc.
7F8D	Unused
8000	Game status buffer entry at 8000
8008	Unused, apart from a disguised JP hidden at $800E-$8010
8014	Load a stage
80B9	Tape loading
81DD	[Messages] Start of stage chatter
8204	Generates engine noise (48K)
8258	Attract mode
837C	Unused
83B5	Indirect calls for 48K/128K features
83CD	Bootstrap / Über main loop
8401	Main loop
852A	CPU driver for attract mode
858C	Pre-game radio screen ("CHASE HQ MONITORING SYSTEM")
85E4	Reveals the perp's car on the pre-game screen
860F	Animate the signal meters
865A	Draw the pre-game screen
86F6	Backdrop shifting instructions
871A	Escape scene setup data
873C	Escape scene
87DC	Sets up the stage
8876	Handle quit, pause or turbo
88D5	Clears the game screen attributes to zero
88E2	Clears the game screen attributes and the game screen to zero
88F2	Starts a sound effect
8903	Drives sound effects
8960	Crash sound effect
89D9	"Thud" sound effect
8A0F	Cornering sound effect
8A36	"Bip" or "Bow" sound effect
8A57	Handle perp caught
8C3A	Fully smashed
8C58	End of stage bonus/score messages
8D8F	Drives transitions (the fade between scenes)
8DF9	Sets up a transition (the fade between scenes)
8E29	Spreads each playfield row's attribute rightwards from column 1
8E42	Draw overlay messages
8E6C	Print a message
8E7E	Setup overlay messages
8E91	Draws the three mugshots to the back buffer when perp is caught
8EB7	Draws a mugshot to the back buffer
8EE7	Draw the smash bar
8F5F	Draws anything that's not the road or the hero car
9052	Draws overhead graphics
916C	Draws stretchy objects, such as trees
924D	Draws tunnel lights via the shared draw_object_left/right drawing code
9278	Draws objects (left hand version)
92E1	Draws objects (right hand version)
949C	Sprite plotter for back buffer, up to 64px wide, 15px high, no mask, no flip
9542	Sprite plotter for back buffer, up to 64px wide, 15px high, no mask, flips
9565	Plot a horizontally flipped sprite, even byte widths
9618	Random number generator
962E	In-game message variables
963F	In-game messages
98A9	In-game chatter structures
9945	Start chatter
9965	Runs chatter, mugshots and noise effect
99EC	Shows the chatter - the alerts and remarks from the game's characters
9A55	Noise in/out effect used for mugshots
9AAB	Plots a face on the screen
9AEC	Plot mini font characters
9BA7	Clear the whole message line
9BCF	Handle "time up", countdown and continue
9CC2	Increments score in proportion to current speed
9CD6	Add a bonus
9D17	Increments the score by (D,E,A)
9D2E	Calculate overtake bonus
9D51	Update scoreboard and flashing lights
9DF4	Toggle the light's BRIGHT bit (HL -> attrs)
9E11	Draws the turbo sprites and updates the displayed speed, time, distance and score
9F47	Plots an 8x15 LED font digit to the screen
9F99	Draw a NUL-terminated string with a specified style
9FB4	Draw one character, to the screen or to the back buffer
A0CC	Keyscan
A139	Game status buffer entry at A139
A27A	[Graphics] 8x7 bitmap font
A399	Checks for scenery collisions
A4B8	Scenery was hit
A4F6	Checks for scenery collisions at a road fork
A579	Lays out roadside objects
A60E	Cycles the three frame counters
A623	Hazard template
A637	Perp car behaviour
A7E7	Horizontal positions and speeds of hazard vehicles
A7F3	Spawns cars
A89C	Returns the range of lanes that cars or hazards should spawn within
A8CD	Update one traffic hazard
A955	Chooses random dirt and stones (not tumbleweeds though)
A97E	Lays out dirt and stones
A9DE	Draws one stone or dirt particle
AA38	Draw the helicopter
AAC6	Move the helicopter
AB33	Drives the helicopter event sequence
AB9A	Spawn hazards
AC3C	Test for collision with hazard
AD0D	Checks for hazard collisions
AD51	Hazard collision
ADA0	Draws all hazards
AECF	Draws the hazard sprites at one depth
B045	Hero car's jump table
B059	Sub-table (another byte pair)
B063	Hero car jumps; gear changing; turbos; off road checks; speed adjustment; turning
B318	Animates the hero car
B457	Draws the "stop" hand shown when the perp is caught
B4CC	Start the chase
B4F0	Smash handling
B549	Draws the debris animation
B58E	Draws the car
B627	Draws a car part
B648	Draw the hero car's turbo smoke
B67C	Draw the cherry light on the car roof
B69E	Draw one frame of the crash, hand and smash animation
B6D6	Draw a masked bitmap at (E,D)
B716	Masked sprite plotter
B76C	Masked sprite plotter which flips
B7EF	Masked + inverted sprite plotter
B828	Horizon scroll rate table
B848	Scroll the horizon
B8D2	Updates the per-frame road level state
B9F4	Lays out the road
BB69	Handle exiting from a road fork
BC3E	Copies the back buffer at $F000 to the screen (and sets attributes)
BDC1	Clears the playfield then sets its attributes
BDFB	Map reader
C0E1	Set up the tunnel
C15B	Tunnel entrance/interior/exit drawing code
C2E7	Subroutine of draw_road
C452	Draws the road
C8BE	Builds a pre-shifted version of the backdrop horizon bitmap
C8E3	Forked road plotting
CBA4	Unknown routine or dead code
CBC5	Selects the near or far backdrop fill continuation by threshold
CBCE	Builds road curvature tables
CD3A	Build the per-row height tables at $E300 and $E336
CDD6	Multiplies C by the top three bits of A, then divides by 8 with rounding
CDEC	Data block at CDEC
CDF4	Pointers to car-on-fire LODs
CE00	Data block at CE00
CE0C	Smoke tables
CE33	Debris tables
CEAA	[Graphics] Debris
CEDA	[Graphics] Hero car drawing data
CFB2	Car graphic anim/adornment table
DF62	[Graphics] LED style numeric font used for scores
DFF8	[Graphics] Mini font used for in-game messages
E0B2	Graphics defns <Byte width, Flags, Height, Ptr, Ptr>
E1E9	Referenced by graphic entry 1 and 10
E2A4	Data for perp escape scene
E2C6	Data for road forks
E2D3	Data for road fork exits
E300	Per-row height table
E320	Data block at E320
E336	Data block at E336
E34B	Horizon values
E34E	Unused
E34F	Data block at E34F
E364	Transition masks
E3F4	Unused
E410	[Graphics] Road edge markings
E4D0	[Graphics] Road lane markings
E500	Outward bend table
E540	Inward bend table
E600	Road/object animation tables
E810	Called once the memory map has been setup
E8FE	"Stop the tape" handler (48K mode only)
E9B4	Messages
EBF7	Renders strings until it hits a NUL byte
EBFF	Renders a string
EC2C	Renders a single character
ECDA	Clears the screen
ECF3	Runs the redefine keys screen (48K mode only)
ED4D	Keyscan
ED6D	Defines a single key
EDD6	Names of keys, two characters per key
EE26	Sinclair joystick input scheme
EE2B	Cursor joystick input scheme
EE30	Keydefs for "SHOCKED<ENTER>"
EE38	Temporary keydefs
EE40	Interrupt setup
EE5E	Reset music
EE6E	Setup the next music pattern
EE9E	Play menu music (48K mode only)
EF19	Interrupt entry point
EF22	Drum sample players
F0C6	White noise generator
F0FE	Music patterns
F111	Music data
F220	128K mode routines and data
F251	Start the siren sound effect (128K)
F269	Play the siren sound effect (128K)
F29D	Silence audio (128K)
F2A2	Write the AY audio registers (128K)
F2B6	Play the engine sound effect
F2F1	Set up turbo sound effect
F2FA	Play turbo sound effect
F32E	Play a sampled sound effect (mostly speech)
F39F	Phase 4 of catching the perp - plays the success music
F3B6	Call a routine in RAM bank 3
F3E2	Replay the four 4K windows at $C000 through the engine sound routine
F414	Reset the paging register
F41B	Attract mode (128K)
F491	Credits / Score messages show in attract mode
F5BE	Marquee initial image
FDBE	Marquee initial attributes
FEBE	Unused