erkyrath.infocom-zcode-terps/apple/zip/warm.g

	PAGE
	SBTTL "--- WARMSTART ROUTINE ---"

	; -------------
	; ZIP WARMSTART
	; -------------

WARM1:	LDA	#10		;CENTER DISPLAY
	STA	CV
	LDA	COL80
	BNE	W1		;80 COL
	LDA	#8		;40 COL
	STA	CH
	BNE	W2		;JMP
W1:	LDA	#27
	STA	CH
	STA	EH
W2:	JSR	BASCAL

	LDA	#HIGH STRYM	;DISP. "THE STORY IS LOADING..."
	LDX	#LOW STRYM
	LDY	#STRYML
	JSR	DLINE

	LDA	#0		; CLEAR ALL Z-PAGE VARIABLES
	LDX	#ZEROPG
ST0:	STA	0,X
	INX
	BNE	ST0

	LDX	#PG2SIZ
ST3:	STA	LRU,X		; CLEAR ALL VARIABLES IN PG 2
	DEX
	BPL	ST3

;	LDA	#0		; INIT THE PAGING TABLE
;	TAX			; = 0

	LDX	#4		; 4 TIMES THRU = 1K
	LDY	#0
	LDA	#HIGH PTABL
	STA	I+HI
	LDA	#LOW PTABL
	STA	I+LO

	LDA	#$FF		; INIT THE PAGING TBL
ST1:	STA	(I),Y
	INY
	BNE	ST1
	INC	I+HI		; NEXT PAGE IN BLOCK
	DEX
	BNE	ST1

	; CLEAR THE TIMESTAMP MAP

	LDA	#HIGH LRUMAP
	STA	I+HI
	LDA	#LOW LRUMAP
	STA	I+LO
	LDX	#4		; = 1K
	LDY	#0
	TYA			; = 0
ST2:	STA	(I),Y
	INY
	BNE	ST2
	INC	I+HI
	DEX
	BNE	ST2

	INC	ZSP		; INIT Z-STACK POINTERS
	INC	OLDZSP		; TO "1"
	INC	SCRIPT		; ENABLE SCRIPTING
	INC	STAMP+LO	; INIT TIMESTAMP

	; GRAB THE FIRST BLOCK OF PRELOAD

	LDA	#HIGH ZBEGIN	; MSB OF PRELOAD START ADDRESS
	STA	ZCODE		; FREEZE IT HERE
	STA	DBUFF+HI	; LSB IS ALWAYS ZERO
	JSR	GETDSK		; [DBLOCK] SET TO Z-BLOCK 0

	; EXTRACT GAME DATA FROM Z-CODE HEADER

	LDX	ZBEGIN+ZENDLD	; MSB OF ENDLOAD POINTER
	INX			; ADD 1 TO GET
	STX	ZPURE+LO	; 1ST "PURE" PAGE OF Z-CODE

	TXA			; ADD START PAGE OF PRELOAD
	CLC			; TO CALC ABSOLUTE START ADDRESS
	ADC	ZCODE		; OF PAGING SPACE
	STA	PAGE0+LO

;	JSR	MEMTOP		; RETURNS TOP RAM PAGE IN [A]
;	SEC
;	SBC	PAGE0		; SUBTRACT ADDRESS OF PAGING SPACE
;	BEQ	NORAM
;	BCS	SETNP		; ERROR IF NOT ENOUGH RAM
;
;	; *** ERROR #0 -- INSUFFICIENT RAM ***
;
;NORAM:	LDA	#0
;	JMP	ZERROR
;

	JSR	MEMTOP		; RETURN TOP RAM PG IN [A/Y]
	PHA
	TYA
	SEC
	SBC	PAGE0+LO
	STA	PMAX+LO
	BEQ	CKHIGH		; LESS OR =, CHECK HIGH BYTE
	BCC	CKHIGH

	PLA
	SBC	PAGE0+HI
	BCC	NORAM		; IF HIGH BYTE IS LESS, NOT ENOUGH MEMORY
	BCS	SETNP		; A-OK

CKHIGH:	PLA
	SBC	PAGE0+HI
	BEQ	NORAM		; LO BYTE NOT ENOUGH, IF NOTHING HERE...
	BCS	SETNP		; OK

	; *** ERROR #0 -- INSUFFICIENT RAM ***

NORAM:	LDA	#0
	JMP	ZERROR

SETNP:	STA	PMAX+HI		; FINISH SETTING # SWAPPING PAGES
	ASL	PMAX+LO		; WORD ALIGN VALUE, 
	ROL	PMAX+HI		; ALWAYS USED THAT WAY IN PAGING

	LDA	ZBEGIN+ZMODE
	ORA	#%00100000	; ENABLE SPLIT-SCREEN
	STA	ZBEGIN+ZMODE

	AND	#%00000010	; ISOLATE STATUS-FORMAT BIT
	STA	TIMEFL		; 0=SCORE, NZ=TIME

	LDA	ZBEGIN+ZGLOBA	; GET MSB OF GLOBAL TABLE ADDR
	CLC			; CONVERT TO
	ADC	ZCODE		; ABSOLUTE ADDRESS
	STA	GLOBAL+HI
	LDA	ZBEGIN+ZGLOBA+1	; LSB NEEDN'T CHANGE
	STA	GLOBAL+LO

	LDA	ZBEGIN+ZFWORD	; DO SAME FOR FWORDS TABLE
	CLC
	ADC	ZCODE
	STA	FWORDS+HI
	LDA	ZBEGIN+ZFWORD+1	; NO CHANGE FOR LSB
	STA	FWORDS+LO

	LDA	ZBEGIN+ZVOCAB	; NOW DO VOCABULARY TABLE
	CLC
	ADC	ZCODE
	STA	VOCAB+HI
	LDA	ZBEGIN+ZVOCAB+1	; LSB SAME
	STA	VOCAB+LO

	LDA	ZBEGIN+ZOBJEC	; NOT TO MENTION
	CLC			; THE OBJECT TABLE
	ADC	ZCODE
	STA	OBJTAB+HI
	LDA	ZBEGIN+ZOBJEC+1	; LSB SAME
	STA	OBJTAB+LO

	; FETCH THE REST OF THE PRELOAD

LDPRE:	LDA	DBLOCK+LO	; CHECK CURRENT BLOCK #
	CMP	ZPURE		; LOADED LAST PRELOAD PAGE YET?
	BCS	WARMEX		; YES, TIME TO PLAY!
	JSR	GETDSK		; ELSE GRAB NEXT Z-BLOCK
	JMP	LDPRE

WARMEX:	LDA	ZBEGIN+ZGO	; GET START ADDRESS OF Z-CODE
	STA	ZPCM		; MSB
	LDA	ZBEGIN+ZGO+1	; AND LSB
	STA	ZPCL		; HIGH BIT ALREADY ZEROED

	LDA	#1		; EXCLUDE STATUS LINE FROM REGULAR DISPLAY
	STA	WTOP
	STA	LINCNT		; FIX FOR 1ST SCREEN

	LDX	WWIDTH		; SET XSIZE TO 1 LESS
	DEX
	STX	XSIZE

	LDA	PSTAT		; CHECK IF RESTART & WAS PRINTING
	BPL	EX2		; NOPE
	LDA	ZBEGIN+ZSCRIP+1	; MAKE IT KEEP PRINTING
	ORA	#%00000001
	STA	ZBEGIN+ZSCRIP+1
	LDA	#2		; RESET PSTAT FOR NEXT TIME
	STA	PSTAT

EX2:	JSR	CLS		; CLEAR SCREEN ...

	; ... AND FALL INTO MAIN LOOP

	END