Antic Magazine 1985 September/Antic_Magazine_1985_09_Antic.atr/revb2c.m65

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0250 ; REV.B TO REV.C CONVERTER¢0260 ; BY MATTHEW RATCLIFF¢0270 ; (c) 1985, ANTIC PUBLISHING¢0280     *=  $0600¢0290     .OPT OBJ¢0300 ;¢0310 ; PUT CODE INTO PAGE 6¢0320 ;¢0330 CASINI = $02    ;VECTOR WE WILL STEAL¢0340 BOOT =  $09     ;CASS/DISK BOOT FLAG¢0350 ; SET BIT 1 AND SYSTEM LOOKS FOR¢0360 ; POST RESET HANDLER CODE POINTED¢0370 ; TO BY CASINI VECTOR. THIS IS¢0380 ; HOW RESET ALWAYS GIVES YOU REV.C¢0390 ; RAM-BASIC.¢0400 GINTLK = $03FA  ;EXTERNAL CART?  DO NOTHING¢0410 RMPNT = $D8     ;ROM/RAM POINTER¢0420 COUNT = $DA     ;BUG FIX COUNT LOC¢0430 PORTB = $D301   ;CONTROL ROM/RAM THRU HERE¢0440 BEGBAS = $A000  ;BASIC ROM STARTS HERE¢0450 ;¢0460 ; STEAL CASSETTE RESET VECTOR¢0470 ; AND POINT HERE FOR NEXT RESET.¢0480 ;¢0490 STEAL LDA # <STEAL¢0500     STA CASINI  ;MUST RESTORE VECTOR¢0510     LDA # >STEAL ;EVERY TIME RESET IS PRESSED¢0520     STA CASINI+1¢0530     LDA GINTLK  ;EXTERNAL CART?¢0540     BEQ CNTNU   ;IF YES, CONTINUE¢0550     RTS         ; IF NO, ABORT¢0560 CNTNU LDA # <BEGBAS ;POINT TO START OF¢0570     STA RMPNT   ;BAD BASIC ROM¢0580     LDA # >BEGBAS¢0590     STA RMPNT+1¢0600 BCOPY LDY #0    ;COPY IT TO RAM¢0610     LDA PORTB   ;BASIC ROM ON PLEASE¢0620     AND #$FD    ;RESET CONTROL BIT=ON¢0630     STA PORTB   ;GOT IT¢0640     LDA (RMPNT),Y ;GET ROM BYTE¢0650     PHA         ;SAVE IT¢0660     LDA PORTB   ;NOW ENABLE THE RAM INSTEAD¢0670     ORA #$02    ;SET CONTROL BIT=OFF¢0680     STA PORTB   ;ROM OFF, RAM ON¢0690     PLA         ;GET ROM BYTE¢0700     STA (RMPNT),Y ;RAM VERSION UPDATED¢0710     INC RMPNT¢0720     BNE BCOPY¢0730     INC RMPNT+1¢0740     LDA RMPNT+1 ;DONE COPYING?¢0750     CMP #$C0    ;END OF BASIC?¢0760     BNE BCOPY   ;NOT YET!¢0770 ; NOW GO FIX THE BUGS!¢0780 FIXBUGS LDX #0  ;BUG TABLE INDEX¢0790     LDA #12     ;12 BUGS TO FIX¢0800     STA COUNT¢0810 FXLOOP LDY #0   ;SETUP RAM POINTERS¢0820     LDA FXTBL,X ;GET ADDR LO BYTE¢0830     STA RMPNT   ;SETUP RAM POINTER¢0840     INX ¢0850     LDA FXTBL,X ;GET ADDR HI BYTE¢0860     STA RMPNT+1¢0870     INX ¢0880     LDA FXTBL,X ;GET CORRECT BYTE¢0890     STA (RMPNT),Y ;TO FIX THE BUG¢0900     INX         ;POINT TO NEXT FIX¢0910     DEC COUNT¢0920     BNE FXLOOP¢0930     LDA BOOT    ;ALL DONE WITH FIXED RAM-BASIC¢0940     ORA #$02    ;RE-HOOK INTO BOOT¢0950     STA BOOT    ;FOR NEXT RESET KEY-PRESS¢0960     RTS ¢0970 ;¢0980 ; ADDRESS,BYTE FIXUP TABLE FOR¢0990 ; REV.B TO REV.C CONVERSION!¢1000 ;¢1010 FXTBL .WORD $A8DF ;ADDRESS¢1020     .BYTE 234   ;WAS 202, NOW 234 IN REV.C¢1030     .WORD $A8E0¢1040     .BYTE 240   ;WAS 208¢1050     .WORD $A8E1¢1060     .BYTE 17    ;WAS 10¢1070     .WORD $A8E2¢1080     .BYTE 234   ;WAS 96¢1090 ;¢1100 ; PEEK (43234)=96 FOR REV.B¢1110 ; THAT IS ADDR $A8E2¢1120 ;¢1130     .WORD $BB29¢1140     .BYTE 0     ;WAS 16¢1150     .WORD $BFF3¢1160     .BYTE 0     ;WAS 44¢1170     .WORD $BFF4¢1180     .BYTE 0     ;WAS 55¢1190     .WORD $BFF5¢1200     .BYTE 0     ;WAS 105¢1210     .WORD $BFF6¢1220     .BYTE 0     ;WAS 110¢1230     .WORD $BFF7¢1240     .BYTE 0     ;WAS 110¢1250     .WORD $BFF8¢1260     .BYTE 0     ;WAS 101¢1270     .WORD $BFF9¢1280     .BYTE 0     ;WAS 114¢1290 ;¢1300 ; ONLY 12 BYTES DIFFERENCE BETWEEN¢1310 ; REV.B & REV.C!¢1320 ;¢1330     .END ¢