00001 *************************
00002 *
00003 * UPARW.ASM
00004 * MDJ 01-23-91
00005 *
00006 * MOVES THE DISPLAY UP
00007 * ONE THIRD PAGE
00008 *
00009 *************************
00010 *
00011 PNV     EQU     $598B
00012 PNTV    EQU     $598D
00013 PMOVET  EQU     $55F8
00014 PMOVEM  EQU     $5603
00015 PMOVEB  EQU     $560E
00016 PPN     EQU     $57B6
00017 PPTT    EQU     $57EE
00018 PPTM    EQU     $5827
00019 PPTB    EQU     $5860
00020 GPAGE EQU       $58E3
00021         ORG     $59B4
00022 UPARW   PSHS    A,X
00023         LDA     PTV     GET CURRENT THIRD CODE
00024         BEQ     UA2     GO IF TOP THIRD
00025         DECA            DECREMENT THIRD CODE
00026         STA     PTV
00027         BNE     UA1     GO IF MIDDLE THIRD
00028         JSR     PMOVET  TOP THIRD
00029         JSR     PPTT
00030         BRA     UA3
00031 UA1     JSR     PMOVEM  MIDDLE THIRD
00032         JSR     PPTM
00033         BRA     UA3
00034 UA2     LDX     PNV     LOAD CURRENT PAGE NUMBER
00035         CMPX    #1      IS IT PAGE NUMBER ONE?
00036         BEQ     UA3     GO IF YES
00037         LDA     #3      RESET THIRD CODE
00038         STA     PTV
00039         LEAX    -1,X    DECREMENT PAGE NUMBER
00040         PSHU    X
00041         JSR     GPAGE   GO GET NEW PAGE
00042         LDX     PNV     GET NEW PAGE NUMBER
00043         PSHU    X
00044         JSR     PPN     GO TYPE PAGE NUMBER TO SCREEN
00045         JSR     PMOVEB  BOTTOM THIRD
00046         JSR     PPTB
00047 UA3     PULS    A,X
00048         RTS
00049 PTV     RMB     2
00050 ZEND    NOP
00051         END
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
