0100 ;******************************
0110 ;**                          **
0120 ;**    SUPERCARTRIDGE DOS    **
0130 ;**     BY ROBERT OPITZ      **
0140 ;**         4/10/85          **
0150 ;**                          **
0190 ;******************************
0200 ;
0210 ;O.S. EQUATES
0220 ;
0230 ICBAL = $0344
0240 ICBAH = $0345
0250 ;
0260 ;DOS EQUATES
0270 ;
0280 DUPFLG = $159D
0290 OPT =   $159E
0300 SFLOAD = $15A4
0310 MEMFLG = $179E
0320 RRDUP = $1801
0330 DUPSYS = $182F
0340 CLOSX = $19AA
0350 CLOS20 = $19B4
0360 DOS =   $2075
0370 ;
0380 ;PROGRAM EQUATES
0390 ;
0400 MSAV =  $1D00
0430 SAVEDUP = $A000
0440 LOW =   $D4
0450 HIGH =  $D6
0460 CART.ON = $D500
0470 CART.OFF = $D5FF
0480 ;
0490 ;  DOS PATCHES
0500     *=  $157A
0510 ;
0520     JMP DUPINIT
0530 ;
0540     *=  $1746
0550 ;
0560 SETSWT
0570     STA CART.OFF ;DISABLE CART
0580     LDA #MSAV&255 ;SET UP
0590     STA LOW     ;INDIRECT
0600     LDA #SAVEDUP&255 ;POINTERS
0610     STA HIGH
0620     LDA #MSAV/256
0630     STA LOW+1
0640     LDA #SAVEDUP/256
0650     STA HIGH+1
0660     LDX #17     ;SWITCH
0693 ;
0695 ; MEMORY SWITCH ROUTINE
0697 ;
0700 SWITCH
0710     LDY #$00
0715 RESWT
0720     LDA (LOW),Y ;PUT LOW BYTE
0730     PHA         ;ON STACK
0740     LDA (HIGH),Y ;SWITCH 1ST BYTE
0750     STA (LOW),Y
0760     PLA         ;LOW BYTE OFF
0770     STA (HIGH),Y ;AND STORE IT
0780     INY 
0790     BNE RESWT   ;NEXT BYTE
0800     INC HIGH+1
0810     INC LOW+1
0820     DEX 
0830     BNE RESWT   ;NEXT PAGE
0835     STA CART.ON ;ENABLE CARTRIDGE
0840     RTS 
0850 ;
0860     *=  $17B6
0870 ;
0880     BEQ RRDUP
0890 GOOD JSR SETSWT ;DO MEM.SAV
0900     DEC MEMFLG  ;SHOW MEM SAVED
0910     BMI RRDUP   ;ALWAYS
0920 ;
0930 ;  COLDSTART ROUTINE
0940 ;
0950 DUPINIT
0960     JSR CLOSX   ;CLOSE IOCB
0970     LDA #$FF    ;CONDITION DOS
0980     STA OPT     ;FLAGS TO LOAD,
0990     STA DUPFLG  ;NOT RUN DUP.SYS
1000     LDX #$10    ;USE IOCB 1
1010     LDA #DUPSYS&255
1020     STA ICBAL,X
1030     LDA #DUPSYS/256
1040     STA ICBAH,X
1050     JSR SFLOAD  ;LOAD DUP.SYS
1060     JSR SETSWT  ;AND MOVE IT
1180     LDA #$00    ;SHOW DUP NOT
1190     STA DUPFLG  ;IN MEMORY
1200     RTS 
1210 ;
1220     *=  $1813
1230 ;
1240     SEC         ;SKIP THIS
1250     BCS CONT    ;SECTION
1260 ;
1270     *=  $183A
1280 ;
1290 CONT DEC DUPFLG ;SHOW DUP IN MEM
1300     JMP DOS     ;AND RUN IT
1310 ;
1320 ; MEMSVQ TELLS DOS IF MEM.SAV
1330 ; IS ACTIVE (Y=1)
1340 ;
1350     *=  $1873
1360 MEMSVQ JSR CLOS20 ;CLOSE IOCB
1370     RTS         ;RETURN Y=1
1380 ;
1390 ; RESTORE SAVED MEMORY
1400 ;
1410     *=  $193F
1420 ;
1430 LDMEM1
1440     JSR SETSWT
1450     RTS 
1460 ;
1470 ;  CHANGE DOS MENU TITLE BAR
1480 ;  TO SUPERCARTRIDGE VERSION
1490 ;
1500     *=  $1F32
1510 ;
1520     .BYTE "SUP"
1530 ;
1540     .END