; The Auto Mono Emulator. V3.00 By Mick West. April 1988. ; Routine to make the ST think it is in mono mode. Needs TOS in ROM ; Makes the system think that there is a mono screen, but actually ; be updating a medium real screen from this under Vblank interrupt ; The XBIOS calls; Physbase,Setscreen and Getrez are revectored. ; Put in an Auto Folder ; Calculates which ROM is in use from the date bytes ($FC0018.L) ; and installs the correct ROM call required from a table. MOVE.L 4(A7),A0 MOVE.L #$8400,D6 ; 32K for the screen ADD.L $C(A0),D6 ; plus the usual space ADD.L $14(A0),D6 ADD.L $1C(A0),D6 MOVE.L D6,-(SP) ; save length of program for later MOVE.W #4,-(SP) TRAP #14 ; Get screen Resolution ADDQ.L #2,SP CMP.W #2,D0 ; If not high then carry on BNE NOTHIGH MOVE.L (SP)+,D6 ; else tidy up the stack MOVE.W #0,-(SP) ; return ok to,GEM TRAP #1 ; Then exit back to desktop NOTHIGH: CLR.L -(SP) MOVE.W #32,-(SP) TRAP #1 ; Enter supervisor mode ADDQ.L #6,SP MOVE.L D0,SAVESTACK ; Save the supervisor stack MOVE.L #MESSAGE,-(SP) ; Address of start of message MOVE.W #9,-(SP) ; Print startup message TRAP #1 ADDQ.L #6,SP MOVE.L $FC0018,D0 ; Get the date bytes from ROM LEA.L ROMTABLE,A0 ; Get start of rom table FINDROM: CMP.L #0,(A0) ; Check if finished table BEQ WRONGROM ; Jump if no more ROMs CMP.L (A0),D0 ; Check date bytes BEQ RIGHTROM ; Jump if they match ADD.L #8,A0 ; Go to next entry in the table BRA FINDROM ; and try that WRONGROM: MOVE.L #WRONG,-(SP) ; Address of start of message MOVE.W #9,-(SP) TRAP #1 ; Print message about crashing now. ADDQ.L #6,SP MOVE.W #1,-(SP) TRAP #1 ; Wait for keypress ADDQ.L #4,SP LEA.L ROMTABLE,A0 ; Default to the old british RIGHTROM: MOVE.L 4(A0),ROMPOKE+2 ; Insert the ROM routine address INLOOP: MOVE.L #INPUT,-(SP) MOVE.W #9,-(SP) ; Print input message TRAP #1 ADDQ.L #6,SP MOVE.B #3,MESSAGE ; Input length = 3 MOVE.L #MESSAGE,-(SP) MOVE.W #10,-(SP) TRAP #1 ; Input number ADDQ.L #6,SP MOVE.W #40,D0 ; Default = 40 TST.B MESSAGE+1 BEQ DEFAULT ; If len=0 CMP.B #1,MESSAGE+1 ; len of 1 not allowed BEQ INLOOP CLR.W D0 MOVE.B MESSAGE+2,D0 ; first digit SUB.W #48,D0 BLE INLOOP ; Too low CMP.W #9,D0 BGT INLOOP ; Too High (>100) MULU #10,D0 CLR.W D1 MOVE.B MESSAGE+3,D1 ; second digit SUB.W #48,D1 BLT INLOOP ; Too low CMP.W #9,D1 BGT INLOOP ; Too high ADD.W D1,D0 CMP.W #80,D0 BGT INLOOP ; Check less than 80 DEFAULT: MOVE.W D0,SCANPOKE+2 SUB.L A5,A5 MOVE.L $044E(A5),MED ; Set MED MOVE.L $B8,XBIOSPOKE+2 ; Get the old XBIOS address and MOVE.L $70,VBLANKPOKE+2 ; VBLANK and insert into new versions MOVE.L #0,MONOPOS ; Set offset to top of screen SCANPOKE: MOVE.W #40,MONOLINES ; Fourty lines per Vblank is default MOVE.W #0,MONOCOUNT ; Counter is set to zero LEA XEND,A2 ; A2 = pos of generated code LEA GEN,A1 ; A1 = pos of instructions to copy MOVE.W #39,D0 ; Generate the code GENMOVE1: MOVE.L (A1),(A2)+ ; Copys 40 of - MOVE.W (A0)+,(A1)+ DBF D0,GENMOVE1 ; and MOVE.W (A2)+,(A1)+ ADDQ.L #4,A1 MOVE.W (A1),(A2)+ ; Move the RTS MOVE.L A2,D0 ; A2 = start of free memory ADD.L #512,D0 ; Force it to a 512 byte boundry AND.L #$FFFFFE00,D0 MOVE.L D0,$044E(A5) ; And that is the monochrome screen MOVE.L D0,MONO ; Set MONO MOVE.W #$0001,-(SP) ; Hardware to medium MOVE.L #-1,-(SP) MOVE.L #-1,-(SP) MOVE.W #5,-(SP) TRAP #14 ; Set medium resolution for hardware ADD.L #12,SP MOVE.B #$0002,$00044C.L ; set high resolution for software MOVE.W #0,$452 ; Turn off VBLANK ROMPOKE: JSR $0 ; The only ROM call, set up rez info MOVE.W #1,$452 ; Turn on VBLANK MOVE.L #XBIOS,$B8 ; Set up the new XBIOS vector MOVE.L #VBLANK,$70 ; And the new VBLANK vector MOVE.L SAVESTACK,-(SP) ; Restore the Supervisor stack MOVE.W #32,-(SP) ; And go back to User mode TRAP #1 ADDQ.L #6,SP MOVE.L (SP)+,D0 ; Tidy stack CLR.W -(SP) ; Exit ok for GEM MOVE.L D0,-(SP) ; Length of program + data space MOVE.W #$31,-(SP) ; terminate and stay resident (TSR) TRAP #1 ; Finished this AUTO program ; This is the new XBIOS routine XBIOS: MOVEM.L A1/A2,-(SP) ; Save A1 and A2 MOVE.L SP,A2 ; A2 = the stack ADD.L #8,A2 ; offset over A1 and A2 BTST #5,(A2) ; Test if called from user mode BNE NOTUSER ; Skip if it is MOVE.L USP,A2 ; Otherwise get A2 = User stack SUB.L #6,A2 ; Offset it as if it were the SSP NOTUSER: MOVE.W $6(A2),D0 ; Get XBIOS instruction code CMP.W #2,D0 ; If it is _PHYSBASE BEQ PHYSBASE ; then jump to new PHYSBASE routine CMP.W #4,D0 ; If it is _GETREZ BEQ GETREZ ; then jump to new GETREZ routine CMP.W #5,D0 ; If it is NOT _SETSCREEN BNE NORM_XBIOS ; Then continue with the normal XBIOS MOVE.W #-1,16(A2) ; Else alter rez.W to -1 (No change) MOVE.L 12(A2),D0 ; Get the ploc.L parameter CMP.L #-1,D0 ; If it is -1 BEQ NORM_XBIOS ; then continue with normal XBIOS MOVE.L D0,MONO ; Otherwise, new value goes to MONO MOVE.L #-1,12(A2) ; Set ploc.L to -1 (no change) BRA NORM_XBIOS ; then norm BIOS deals with lloc.L PHYSBASE: MOVE.L MONO,D0 ; Get address of mono screen MOVEM.L (SP)+,A1/A2 ; Tidy stack RTE ; Return mono screen location GETREZ: MOVE.W #2,D0 ; Pretend we are in mono resolution MOVEM.L (SP)+,A1/A2 ; Tidy the stack RTE ; Return code for mono resolution NORM_XBIOS: MOVEM.L (SP)+,A1/A2 ; Tidy the stack up XBIOSPOKE: JMP $0.L ; And jump into the normal XBIOS ; This is the new VBLANK routine VBLANK: MOVEM.L D0-D7/A0-A6,-(SP) ; Save all registers MOVE.W #$333,$FF8242 ; Set up colours, grey for thin lines MOVE.W #$333,$FF8244 ; (1 vert mono pixel = 1 grey med pix) BTST #0,$FF8240 ; Check inverted BEQ INVERT ; Jump if so MOVE.W #$777,$FF8240 ; White background (normal) MOVE.W #$000,$FF8246 ; Black ink BRA NOINVERT INVERT: MOVE.W #$000,$FF8240 ; Black background (inverted) MOVE.W #$777,$FF8246 ; White ink NOINVERT: CLR.L D0 MOVE.B $FF8201,D0 ; Video base high LSL.L #8,D0 ; times 256 MOVE.B $FF8203,D0 ; Plus video base low LSL.L #8,D0 ; All times 256 MOVE.L D0,A3 ; Is the address of the Real screen MOVE.L MONO,A0 ; A0 = virtual mono screen MOVE.L MED,A1 ; A1 = real medium screen CMP.L A1,A3 ; Check if the real screen has moved BEQ MEDOK ; Skip this if not MOVE.L A3,A0 ; Get the new real screen address MOVE.L A0,MONO ; Set MONO From this MOVE.L A1,D0 ; And put the real screen back LSR.L #8,D0 ; to its origional position MOVE.B D0,$FF8203 LSR.L #8,D0 MOVE.B D0,$FF8201 MEDOK: MOVE.L A0,A2 ; A2 = mono start ADD.L #80,A2 ; plus 80, on to next line MOVE.L MONOPOS,D2 ; Get position in the screen RAM ADD.L D2,A0 ; Offset position in mono screen ADD.L D2,A2 ; And the other mono position ADD.L D2,A1 ; Offset pos in real medium screen MOVE.W #10,D1 ; default 10 lines / Vblank TST.B $43E ; Test flock system variable BNE COPYMOVE ; Set speed to 10 if using disk drive TST.B $9BE ; Test if motor on ? (not sure) BNE COPYMOVE ; Jump if using disk MOVE.W MONOLINES,D1 ; Otherwise get preset speed COPYMOVE: BSR XEND ; combine and move two mono lines ADD.L #80,A0 ; both need moving down another line ADD.L #80,A2 ; in the mono screen ADD.L #160,MONOPOS ; move down one medium/two mono lines ADD.W #1,MONOCOUNT ; count medium lines dome CMP.W #200,MONOCOUNT ; Done 200 medium/ 400 mono ? BNE NOT200 ; if not then skip MOVE.L #0,MONOPOS ; otherwise reset ram offset SUB.L #32000,A0 ; MONO position back to top of screen SUB.L #32000,A1 ; and the same for MEDIUM SUB.L #32000,A2 ; and the other MONO position MOVE.W #0,MONOCOUNT ; reset the counter NOT200: DBF D1,COPYMOVE ; loop round MONOLINES times VBLEXIT: MOVEM.L (SP)+,D0-D7/A0-A6 ; Restore all registers VBLANKPOKE: JMP $0.L ; Jump to normal VBLANK routine ; The following bits of code are not called but are used to calculate ; a large chunk of code to combine two mono lines into one medium one. GEN: MOVE.W (A0)+,(A1)+ ; Move one Mono line to one Medium MOVE.W (A2)+,(A1)+ ; line on both colour planes times 40 RTS EVEN SAVESTACK: DC.L 0 MONO: DC.L 0 ; Base address of mono screen MED: DC.L 0 ; Base address of medium screen MONOPOS: DC.L 0 ; Offset in both screens in bytes MONOLINES: DC.L 0 ; Pairs of mono lines to do per VBLANK MONOCOUNT: DC.L 0 ; Count of pairs done so far XEND: nop ; Position of calculated code MESSAGE: DC.B 27,'E','The Mono Emulator - Mick West 1988',13,10 DC.B 'V3.00. Should be in AUTO Folder',13,10,13,10 DC.B 'This is Shareware',13,10 DC.B 'Send Money and Problems to:',13,10 DC.B '27 Lynton Drive,',13,10 DC.B 'Shipley,',13,10 DC.B 'BD18 3DJ',13,10 DC.B 'ENGLAND',13,10,13,10 DC.B 'Feel free to give away copies of this',13,10 DC.B 'But please copy the whole folder',13,10,13,10,0 INPUT: DC.B 13,10 DC.B 'Enter speed (10 to 80, return = 40) ',0 WRONG: DC.B 'Sorry I do not recognise this Version of',13,10 DC.B 'TOS, I will carry on and probably crash.',13,10 DC.B 'Please read MONOEMU.DOC. Press a Key',13,10,0 EVEN ; This is a table of ROM creation dates ($FC0018) and the corresponding ; ROM routine to set up the resolution information. If you can add to ; this then please let me know the two numbers. ; The ROM routine is called as part of XBIOS _SETSCREEN routine, ; it is the last routine called. See MONOEMU.DOC for more info. ROMTABLE: DC.L $11201985,$00FCA76A ; Old British (1.08) DC.L $04221987,$00FCA914 ; New British (1.09) ; Insert any more here with comments, leave the following terminator DC.L 0,0 ÿ€Ÿ$VÂH‚gºNîŽN®ê”Aí€ ü0¼