Up'n Down (Apple II)

Up'n Down
Sviluppatore: Sega Publisher: Sega Piattaforma: Apple II Rilasciato negli Stati Uniti: 1984 Questo gioco contiene codice sorgente non compilato. Questo gioco ha un messaggio nascosto dello sviluppatore. Questo gioco ha crediti nascosti degli sviluppatori.

Developer Message

Track 0, Sector 1 includes a small message from the developers:

HELLO THERE THIS IS THE CREATOR OF U&D.
THIS SECTOR ON THE DISK IS OF NO VALUE
AND THERE IS NO SENSE EVEN LOOKING AT IT.
SO WHAT ARE YOU DOING!

PROGRAM BY ERIC J. POPEJOY AND KEN O. JORDAN.

KEN ALSO GOES BY 'KEYBOARD OR JOYSTICK'.
HAPPY CRACKING!

(Source: 4 a.m.)

Source Code

Also present is a decent chunk of source code on Sector 29.

 BEQ ZRTS
 JMP COLL10
ZRTS RTS
*
* SEE IF TIME TO ADD A NEW CAR
*
NEWCAR
 INC TOSLOW
 LDA TOSLOW
 CMP #$40
 BCC SLOWOK
 LDA #$30
 STA TOSLOW
 LDA #$03
 BNE NEWC30
SLOWOK LDA OBYSPD
 ADC SCORL
 ADC SCORM
 ADC HIGHH
 ADC $C100
 ADC $C300
 ADC $C200
 LDX DIFFCLT
 AND DIFTBL,X
 BNE ZRTS
 LDA LEVEL
 CMP #$01
 BEQ ZRTS ;NO RANDOM CARS ON LEVEL 1
 LDA $C100
 EOR $C200
 EOR $C300
 AND #$0F
 TAX
 LDA OKNEW,X
NEWC30 PHA
 CMP #$07
 BNE NEWC35
 LDX #$0F
NEWC32 CMP OBTYP,X
 BEQ NEWC42 ;FLAG CAR IS ON SCREEN
 DEX
 BPL NEWC32
NEWC35
 LDX #$0F
NEWC40 LDA OBTYP,X
 BMI NEWC45
 DEX
 BNE NEWC40
NEWC42 PLA
 RTS  ;ALL FULL
NEWC45 PLA
 STA OBTYP,X
 LDA CARSPD
 CMP #$20
 BCS NEWC50
 CMP #$18
 BCC NEWC49
 LDA CURPAG
 BNE NEWC50
NEWC49 LDA #$18
 HEX 2C HEX EAT
NEWC50 LDA #$C0
 STA OBY,X
 LDA OBTYP,X
 TAY
 LDA BEGSPD,Y
 STA OBYSPD,X
 LDA $C050
 ADC $C057
 AND #$1F
 CLC
 ADC #$02
 PHA
 LDY OBY,X
 BMI NEWC52
 LDY #$20
 BNE NEWC54
NEWC52 LDY #$BE
NEWC54
 LDA P1L,Y
 STA SHAPE
 LDA P1H,Y
 CLC
 ADC CURPAG
 STA SHAPE+1
 PLA
 TAY
NEWC60 LDA (SHAPE),Y
 BEQ NEWC62
 DEY
 BNE NEWC60
 LDY #$27
NEWC65 LDA (SHAPE),Y
 BEQ NEWC62
 DEY
 BNE NEWC65
 LDA #$FF
 STA OBTYP,X
 RTS
NEWC62
 LDA MUL4TBL,Y
 STA OBX,X
 LDA #$18
 STA OBYSPD,X
 RTS
DIFTBL HEX FF7F7F3F3F1F1F0F0F0707070303030303

POINT HEX 0004040400040404
      HEX 0406060404040000

********************************
*                              *
*  READ STUFF FROM THE DISK    *
*                              *
********************************
DISKREAD LDA DTRACK,X
 STA TRACK
 LDA DSE