** Code By MEGABASS ** Thanx to Mark, Mike, Neil and Spanner. *--------------------------------------------------------------------------- OPT C- Case Independant *--------------------------------------------------------------------------- include sys:include/hardware/custom.i *--------------------------------------------------------------------------- Number = 2-1 number of colours for the picture Custom = $dff000 Base Address of cutom chips Port_A = $bfe001 Mouse and Joystick Register KeyBoard = $bfec01 Whats this Left_Mouse = 6 Rodents Left-Eye Joy1 = 7 Blast Em' Screen_Size = 256*40 Screen Size For Blitter Logo_Size = 64*8 Logo (BOB) Size For Blitter *--------------------------------------------------------------------------- * Main Calling Routine *--------------------------------------------------------------------------- movem.l a0-a6/d0-d7,-(a7) Save all Registers move.l a7,Stack_Save Save Pointer lea Custom,a5 Move Base-Address jsr Kill_OS Disable Multitasking etc. jsr Setup Setup Bitplanes etc. jsr Main Mouse Wait etc. jsr Help_OS Enable Multitasking etc. move.l Stack_Save,a7 Restore Pointer movem.l (a7)+,a0-a6/d0-d7 Restore Registers rts *--------------------------------------------------------------------------- Kill_OS: *--------------------------------------------------------------------------- move.l 4.w,a6 Move Execbase jsr -132(a6) Open Library move.l (a6),a6 Graphics move.l (a6),a6 library move.l a6,a0 move.l 38(a0),Sys_Copper Store CLI Copper move.w intenar(a5),Sys_Intena Save INTERUPT State move.l $68.w,Sys_Level2 Save LEVEL 2 move.l $6c.w,Sys_Level3 Save LEVEL 3 move.w dmaconr(a5),Sys_Dma Save present state move.w #$7fff,dmacon(a5) Clear all DMA move.w #%1000001111000000,dmacon(a5) Select DMA rts Return to calling Routine *--------------------------------------------------------------------------- Setup: *--------------------------------------------------------------------------- move.l #Screen,d0 Load Screen into d0 move.w d0,Pl1l Move LO word out swap d0 Swap LO <-> HI move.w d0,pl1h Move HI word out swap d0 add.l #Screen_Size,d0 move.w d0,Pl2l Move LO word out swap d0 Swap LO <-> HI move.w d0,pl2h Move HI word out swap d0 add.l #Screen_Size,d0 move.w d0,Pl3l Move LO word out swap d0 Swap LO <-> HI move.w d0,pl3h Move HI word out swap d0 add.l #Screen_Size,d0 move.w d0,Pl4l Move LO word out swap d0 Swap LO <-> HI move.w d0,pl4h Move HI word out swap d0 add.l #Screen_Size,d0 move.w d0,Pl5l Move LO word out swap d0 Swap LO <-> HI move.w d0,pl5h Move HI word out move.l #Copperlist,Cop1lc(a5) Move My Copper in clr.w Copjmp1(a5) Strobe Copper to Start rts Return to calling Routine *--------------------------------------------------------------------------- Main: *--------------------------------------------------------------------------- cmpi.b #$f0,VHPosr(a5) Compare VHPOSR to 240 bne.s Main Not Equal GO to Main bsr Start_Blitter Go and Start Blit_op btst #Left_Mouse,Port_A Check for mouse bne Main Not Equal GO to Main rts Return to calling Routine *--------------------------------------------------------------------------- Start_Blitter: *--------------------------------------------------------------------------- lea Logo,a0 lea Screen,a1 bsr Blit_Table_Loop Get Bob Position add.l d3,a1 Adds contents of d3 from table below moveq.w #4,d0 SBL: ;Start Blit Loop for each Plane bsr Go_Blit_1 do this 4* to blit each plane dbra d0,SBL Do all Bitplanes (5-1) rts *--------------------------------------------------------------------------- Blit_Table_Loop: *--------------------------------------------------------------------------- move.l Table_Ptr,a3 Moves Table Pointer to a3 move.w (a3)+,d3 Moves first word out cmp.w #$fffe,d3 Compares for end of Table bne Return Not met, so branch move.l #Blit_Pos_Table,Table_Ptr bra Blit_Table_Loop Branch until $fffe Return: move.l a3,Table_Ptr Store A3 rts Return to Start_Blitter Table_Ptr: dc.l Blit_Pos_Table Pointer to Position table Blit_Pos_Table: dc.w 7680,5120,2560,0,8 Screen Positions dc.w 16,24,32,2592,5152 for Blitter operations dc.w 7712,7704,7696,7688 dc.w 5128,2568,2576,2584 dc.w 5144,5136,$fffe *--- The Formula I`ve used for the position Calculations is as follows:- *--- the BOB = 64 lines deep, The width of the screen is 40 bytes wide *--- so to Blit one directly below another you would do:- *--- 64*40 = 2560 (Hex $0A00), So in the above table the 7680 = *--- 64*40*3 (Bottom blit), The 8, 16, 24 and 32 are bytes, and position *--- the blits along the top line. *--------------------------------------------------------------------------- Go_Blit_1: *--------------------------------------------------------------------------- ; Thanx to Mike and Neil for all the help in understanding the blitter bsr Wait_Blit Is Blitter ready move.l a0,BltApt(a5) Set BLTAPTH = A0 = BOB move.l a1,BltDpt(a5) Set BLTDPTH = A1 = SCREEN move.w #0,BltAmod(a5) Set BLTAMOD = Clear move.w #32,BltDmod(a5) Set BLTDMOD = to get to next line move.w #$ffff,BltAfwm(a5) Set BLTAFWM = No MASKING move.w #$ffff,BltAlwm(a5) Set BLTDLWM = No MASKING move.w #$09f0,Bltcon0(a5) Set BLTCON0 = straight A to D move.w #0,Bltcon1(a5) Set BLTCON1 = Clear move.w #64*64+4,Bltsize(a5) Set BLITSIZE 64x64/4 (decimal 4100) add.l #Logo_Size,a0 Variable at top add.l #Screen_Size,a1 Variable at top rts Return to calling Routine *--------------------------------------------------------------------------- Wait_Blit: *--------------------------------------------------------------------------- btst #14,Dmaconr(a5) Is Blitter free ? bne.s Wait_Blit No, Not yet!! rts Return to calling Routine *--------------------------------------------------------------------------- Help_OS: *--------------------------------------------------------------------------- move.l $4,a6 jsr -138(a6) move.w #$7fff,intena(a5) move.l Sys_Level2,$68.w move.l Sys_Level3,$6c.w move.w Sys_Intena,d0 bset #$f,d0 Reset Interupt enable move.w d0,intena(a5) move.l Sys_Copper,cop1lc(a5) clr.w copjmp1(a5) move.w Sys_Dma,d0 bset #$f,d0 Reset DMA move.w d0,dmacon(a5) rts Return to calling Routine *--------------------------------------------------------------------------- * Variables and Includes *--------------------------------------------------------------------------- Stack_Save: dc.l 0 Sys_Copper dc.l 0 Sys_Level2 dc.l 0 Sys_Level3 dc.l 0 Off_Set dc.l 0 Sys_Dma dc.w 0 Sys_Intena dc.w 0 Sys_Intreq dc.w 0 *--------------------------------------------------------------------------- SECTION LOWMEM,DATA_C *--------------------------------------------------------------------------- Copperlist *--------------------------------------------------------------------------- dc.w $0001,$fffe dc.w diwstrt,$2c81 Start of Screen Window dc.w diwstop,$2cc1 Screen window Finish dc.w ddfstrt,$38 Fetch Data dc.w ddfstop,$d0 Stop Fetching Data dc.w bplcon0,$5200 Set 1 low-res bitplane dc.w $0180,$0000,$0182,$05ff,$0184,$0001,$0186,$0011 dc.w $0188,$0012,$018a,$0023,$018c,$0233,$018e,$0003 dc.w $0190,$0113,$0192,$0226,$0194,$0337,$0196,$0035 dc.w $0198,$0256,$019a,$0110,$019c,$0210,$019e,$0320 dc.w $01a0,$0310,$01a2,$0430,$01a4,$0540,$01a6,$0850 dc.w $01a8,$0640,$01aa,$0740,$01ac,$0751,$01ae,$0861 dc.w $01b0,$0a72,$01b2,$0850,$01b4,$0862,$01b6,$0a71 dc.w $01b8,$0d93,$01ba,$0fc5,$01bc,$0530,$01be,$0000 dc.w $e0 Bitplane 1 High word Pl1h dc.w 0,$e2 Bitplane 1 Low word Pl1l dc.w 0,$e4 Pl2h dc.w 0,$e6 Pl2l dc.w 0,$e8 Bitplane 1 High word Pl3h dc.w 0,$ea Bitplane 1 Low word Pl3l dc.w 0,$ec Pl4h dc.w 0,$ee Pl4l dc.w 0,$f0 Bitplane 1 High word Pl5h dc.w 0,$f2 Bitplane 1 Low word Pl5l dc.w 0 dc.w $ff99,$fffe,$ffdd,$fffe Enable PAL dc.w $ffff,$fffe Impossible position even *--------------------------------------------------------------------------- Logo: incbin Source:bitmaps/KING.raw *--------------------------------------------------------------------------- even Screen: dcb.b 256*40*5,0 end