Ever wanted to replace the vanilla timer with a Centiseconds timer akin to Sonic CD/ Chaotix/ Mania/ 3 A.I.R in your hack? This short tutorial is aimed towards Hivebrain ASM68K users with code ported from ReadySonic with Mercury's permission. First you'll need to download the HUD Centiseconds Resources zip file attached below and replace the files to their respective folders in your disassembly. Next, open sonic1.asm and under Level_LoadObj insert this line between the clear time and lives counter flags: Code: move.w d0,($FFFFFE20).w ; clear rings move.l d0,($FFFFFE22).w ; clear time move.b d0,($FFFFFEBF).w ; value used to increment centiseconds move.b d0,($FFFFFE1B).w ; clear lives counter Make sure to delete this line in loc_39E8: Code: move.b #1,($FFFFFE1E).w in Level_StartGame, add this line above bclr #7,($FFFFF600).w: Code: move.b #1,($FFFFFE1E).w ; update time counter bclr #7,($FFFFF600).w ; subtract 80 from screen mode Next, go to Cont_GotoLevel and insert this line between clear time and clear score: Code: move.l d0,($FFFFFE22).w ; clear time move.b d0,($FFFFFEBF).w ; value used to increment centiseconds move.l d0,($FFFFFE26).w ; clear score Go to Obj21_Main, and change move.w #$6CA,2(a0) to Code: move.w #$6BA,2(a0) Next, replace everything from Hud_ChkTime to Hud_End with this: Code: Hud_ChkTime: tst.b ($FFFFFE1E).w ; does the time need updating? beq.w Hud_ChkLives ; if not, branch ;Mercury HUD Centiseconds (bsr.s => bsr.w) ported by -paranoimia- tst.w ($FFFFF63A).w ; is the game paused? bne.w Hud_ChkLives ; if yes, branch ;Mercury HUD Centiseconds (bsr.s => bsr.w) ported by -paranoimia- lea ($FFFFFE22).w,a1 cmpi.l #$93B63,(a1)+ ; is the time 9'59"99? beq.w TimeOver ; if yes, branch ;Mercury HUD Centiseconds (bsr.s => bsr.w) ported by -paranoimia- move.b ($FFFFFEBF).w,d1 addi.b #1,d1 cmpi.b #3,d1 bne.s Cent_Skip move.b #0,d1 Cent_Skip: move.b d1,($FFFFFEBF).w cmpi.b #2,d1 beq.s Cent_Skip2 addi.b #1,d1 Cent_Skip2: add.b d1,-(a1) cmpi.b #100,(a1) bcs.s Hud_DoCent move.b #0,(a1) addq.b #1,-(a1) cmpi.b #60,(a1) bcs.s loc_1C734 move.b #0,(a1) addq.b #1,-(a1) cmpi.b #9,(a1) bcs.s loc_1C734 move.b #9,(a1) loc_1C734: move.l #$5E400003,d0 moveq #0,d1 move.b ($FFFFFE23).w,d1 ; load minutes bsr.w Hud_Mins move.l #$5EC00003,d0 moveq #0,d1 move.b ($FFFFFE24).w,d1 ; load seconds bsr.w Hud_Secs Hud_DoCent: move.l #$57800003,d0 ;Mercury Macros ported by -paranoimia- moveq #0,d1 move.b ($FFFFFE25).w,d1 ; load centiseconds bsr.w Hud_Secs Hud_ChkLives: tst.b ($FFFFFE1C).w ; does the lives counter need updating? beq.s Hud_ChkBonus ; if not, branch clr.b ($FFFFFE1C).w bsr.w Hud_Lives Hud_ChkBonus: tst.b ($FFFFF7D6).w ; do time/ring bonus counters need updating? beq.s Hud_End ; if not, branch clr.b ($FFFFF7D6).w move.l #$6E000002,($C00004).l moveq #0,d1 move.w ($FFFFF7D2).w,d1 ; load time bonus bsr.w Hud_TimeRingBonus moveq #0,d1 move.w ($FFFFF7D4).w,d1 ; load ring bonus bsr.w Hud_TimeRingBonus Hud_End: rts then add this new subroutine below LoadZero: Code: ; --------------------------------------------------------------------------- ; Subroutine to load " on the HUD ported by -paranoimia- ; --------------------------------------------------------------------------- ; ||||||||||||||| S U B R O U T I N E ||||||||||||||||||||||||||||||||||||||| Hud_LoadMarks: ; XREF: HUD_Update move.l #$57400003,($D00004).l ;locVRAM $D740 lea Hud_TilesMarks(pc),a2 move.w #2,d2 bra.s loc_1C83E ; End of function Hud_LoadMarks in Hud_Base insert this below bsr.w Hud_Lives: Code: bsr.s Hud_LoadMarks and finally, below End of function Hud_Base, replace this: Code: Hud_TilesBase: dc.b $16, $FF, $FF, $FF, $FF, $FF, $FF, 0, 0, $14, 0, 0 Hud_TilesZero: dc.b $FF, $FF, 0, 0 with this: Code: Hud_TilesMarks: dc.b $1A, 0, 0, 0 Hud_TilesBase: dc.b $16, $FF, $FF, $FF, $FF, $FF, $FF, 0, 0, $18, 0, 0 Hud_TilesZero: dc.b $FF, $FF, 0, 0 Now you should have a functioning Centiseconds Counter in your hack. Bug to note: If the player were to pass a checkpoint then lose a life and wait until the timer reached 9'59"99, the timer will reset back at the 9 minute mark instead of prompting the Time Over routine which is present in the original ReadySonic source. Credits: Mercury for the ReadySonic Source Hivebrain ASM68K code porting by paranoimia
