Doubleback RAM Usage

The game works with 4K of RAM, which means it only uses one screen buffer.

Stack builds to lower from 0150.

Screen uses 0400 to 1000.

B4	numPlayers	0 for ONE PLAYER, 1 for TWO PLAYER
B5	numLives	Current number of lives
B6	player	Current player number (0 or 1)
B7:B8	p1Score	Player one score
B9:BA	p2Score	Player two score
BB:BC	highScore	Highest score since power on
BD	collision	1 if the player touches a game object
BE	endOfPlayer	Offset to the end of the player's point buffer
BF	origPixel	For collision detection
C0	objCounter	Counter temporary for looping through objects
C1	loopStart	Temporary for noting where player loop starts
C2	transY	Temporary for translating the player's Y coordinate
C3	nontouch	Temporary for counting number of non-overlapping points
C4	numLooped	number of objects currently looped by player
C5	digitColor	number can be printed white on black or black on white
C6	loopScoreCnt	counter for showing the loop score
C7	hasLoopScore	non-zero if there is a loop score to display
C8:C9	loopScoreTmp	sum of scores for objects currently looped by player
CA:CB	loopScoreShown	the loop score being shown
CC:CD	loopScoreLoc	screen location of the loop score being shown
CE	liveObjCnt	Number of live game objects on the screen
CF	skullCount	number of skulls being shown
D0	totalLoops	total number of loops made in round
D1	nextObjTime	count to wait before making another object
D2:D3	nextFreeObj	next free game object memory slot
D4	cycleCount	used to pace the objects so not all update at once
D5	flashCount	used to time the flashing "one" or "two" during game play
D6	flashType	used to flash "one" or "two" during game play (FF draws word, 00 draws space)
D7	random	Random value. Entropy: waits for VBLANK, player's X axis input
D8:DD	playerObj	Player object (for drawing the point)
DE:E3	eraseObj	Utility object for erasing points
E4:E9	splashObj	Utility object for messages and cursive drawing
EA:EF	gameObj	Utility object for the current game object
0160:1FFF	gameObjs	Game objects
0200:02FF	playerLine	Points for the player's line
0380:0390	pixelMask	Pixel mask table