Find Next Screen
;*********************************************************************
;* JUMP 5000 PICK WHICH SCREEN TO RUN?
;* SCREENTABLE: ; Table of screen values used in BAS5010
;* fdb 1,1,3,4,2,1,1,4,2,5,1,1,1,6,1,1,5,1,1,6,0
;* Brief description
;*
;* I/O: what is expected and produced
;*
;* Calling Convention: how is this called?
;*
;* Returns:
;*
;* Stack Usage: (when needed) structure of stacked data
;*
;* Calls: Info about routines called
;*
;* Changes: registers destroyed.
;*********************************************************************
BAS5000: ; 5000 REM**
BAS5005: ; FIXME 5005 POKE&HF5E5,&HE3:PM=1:CR=4:SS=0
clr NEXTSCREEN ; FIXME F5E5 LOADS AS D4 - CHANGED TO E3
lda #1 ; FIXME constants can be made into config variables
sta PM ; NUMBER ITEMS PER CATEGORY TO 1
lda #4 ; FIXME constants can be made into config variables
sta CR ; 4 CREW REMAINING
clr SS ; SHOW SCREEN 0
BAS5006: ; FIXME 5006 GOSUB 6700:EE=0
; FIXME SETUP F53B TO JR 0xF569
clr EE ; FIXME EE = 0 WHAT IS EE?
BAS5010: ; 5010 EXEC&HF5B8
; ############################################################################
ASMF5B8: ; LDX 0xF5E5 ;F5B8 2A E5 F5 LD HL,(0xF5E5)
; LEAX 1,X ;F5BB 23 INC HL
; TFR L,A ;F5BC 7D LD A,L
; CMPA #$ E ;F5BD FE E4 CP 0xE4
; LBNE 0xF5C3 ;F5BF 20 02 JR NZ,0xF5C3
; TFR 0xD0,L ;F5C1 2E D0 LD L,0xD0
; LDA ,X ;F5C3 7E LD A,(HL)
; STA 0xF5E7 ;F5C4 32 E7 F5 LD (0xF5E7),A
; STX 0xF5E5 ;F5C7 22 E5 F5 LD (0xF5E5),HL
; RTS ;F5CA C9 RET
; ### TABLE OF SCREEN/LEVEL VALUES?
; TFR 0x0301,U ;F5D0 01 01 03 LD BC,0x0301
; INCB ;F5D3 04 INC B
; STA ,U ;F5D4 02 LD (BC),A
; TFR 0x0401,U ;F5D5 01 01 04 LD BC,0x0401
; STA ,U ;F5D8 02 LD (BC),A
; DECB ;F5D9 05 DEC B
; TFR 0x0101,U ;F5DA 01 01 01 LD BC,0x0101
; TFR 0x01,B ;F5DD 06 01 LD B,0x01
; TFR 0x0105,U ;F5DF 01 05 01 LD BC,0x0105
; TFR 0x0006,U ;F5E2 01 06 00 LD BC,0x0006
; BCS > ;F5E5 -
; LBSR 0x01F5
; ! *** Jump here ;**** D4 F5 01 CALL NC,0x01F5
ldb NEXTSCREEN ; load the value of the offset into the table
incb ; move the offset one more
cmpb #20 ; did we hit 00 at the end of the table?
bne EXIT5010 ; not at the end of the table, use the B we got
clrb ; yep, hit end of table, so reset offset to 0 back at start of table
EXIT5010: stb NEXTSCREEN ; save our offset to use in B
ldx #SCREENTABLE ; load address of table of screens to show in order
abx ; now get that table value address read
lda ,X ; load table value into accumulator
BAS5020: ; 5020 ON PEEK(&HF5E7) GOSUB 100,2000,4000,6000,6500,8800,6000,8800
; MOVE THROUGH TABLE OF SCREENS AS GAME PROGRESSES?
; F5E7 LOADS AS 01 TO GO TO MAIN GAME LOOP FIRST
; SCREEN 1 - 100 MAIN
; SCREEN 2 - 2000 TIME TRIAL
; SCREEN 3 - 4000 DEMO1
; SCREEN 4 - 6000 TIME TRIAL
; SCREEN 5 - 6500 GRAPHIC MULTICOLOR ALIEN SITTING STILL
; SCREEN 6 - 8800 GRAPHIC RED ALIEN BOUNCING BACK AND FORTH
; SCREEN 7 - 6000 GRAPHIC MULTICOLOR ALIEN SITTING STILL
; SCREEN 8 - 8800 GRAPHIC RED ALIEN BOUNCING BACK AND FORTH
; FIXME replace this mess with a jump table by offset
; SCREEN 7 AND 8 in GOSUB are never called by number from table
cmpa #1 ; is next screen #1?
bne CHKSCN2 ; no, go check next
jsr BAS0100 ; yes, gosub line 100 - main game screen
jmp BAS5025 ; go check EE when done
CHKSCN2:
cmpa #2 ; is next screen #2?
bne CHKSCN3 ; no, go check next
jsr BAS2000 ; gosub line 2000 - main time trial screen
jmp BAS5025 ; go check EE when done
CHKSCN3:
cmpa #3 ; is next screen #3?
bne CHKSCN4 ; no, go check next
jsr BAS4000 ; yes, gosub line 4000 demo 1
jmp BAS5025 ; go check EE when done
CHKSCN4:
cmpa #4 ; is next screen #4?
bne CHKSCN5 ; no, go check next
jsr BAS6000 ; yes, gosub line 6000 - time trial intro
jmp BAS5025 ; go check EE when done
CHKSCN5:
cmpa #5 ; is next screen #5?
bne CHKSCN6 ; no, go check next
jsr BAS6500 ; yes, gosub line 6500 - graphic alien sitting still
jmp BAS5025 ; go check EE when done
CHKSCN6:
cmpa #6 ; is next screen #6?
bne CHKSCN7 ; no, go check next
jsr BAS8800 ; yes, gosub line 8800 - graphic alien bouncing around
jmp BAS5025 ; go check EE when done
; FIXME we should never fall through here
CHKSCN7: bra CHKSCN7 ; ERROR - HALT
CHKSCN8: bra CHKSCN8 ; ERROR - HALT
BAS5025: ; 5025 IF EE=1 THEN GOTO 5000
lda EE ; load EE
cmpa #1 ; compare EE to 1
bne BAS5030 ; not equal, go to next line 5030
jmp BAS5000 ; was equal, go to line 5000
BAS5030: ; 5030 GOTO 5010
jmp BAS5010
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