Centiseconds in Sonic 1

To download the Source Code and the compiled ROM, click here:
http://goo.gl/bphDe

If you want add the Centiseconds in Sonic 1, follow the step below.


In sonic1.asm, go to Hud_ChkLives and add this line:

Code:

      bsr.s   CentiSecond

Now below this code:

Code:

Hud_End:
      rts

Add these lines:

Code:

CentiSecond:
      move.l   #$75400003,d0
      moveq   #0,d1
      move.b   ($FFFFFE25).w,d1 ; load   frames
      mulu.w   #$1AA,d1
      lsr.l   #8,d1
      jsr   Hud_Secs
      rts

In \_maps\obj21.asm, change all the code by this code fully commented:

Code:

; ---------------------------------------------------------------------------
; Sprite mappings - SCORE, TIME, RINGS
; ---------------------------------------------------------------------------
      dc.w byte_1C5BC-Map_obj21, byte_1C5F0-Map_obj21
      dc.w byte_1C624-Map_obj21, byte_1C658-Map_obj21
      
      ; Y-Pos, layout, VDP (2bytes - plane, pallet line (2bits), flip, mirror, first tile (11bits) - ), X-Pos
byte_1C5BC:   dc.b $C
      dc.b $80, $D, $80, 0, 0      ; SCOR
      dc.b $80, $D, $80, $18,   $20   ; E + score left numbers
      dc.b $80, $D, $80, $20,   $40   ; score right numbers
      dc.b $90, $D, $80, $10,   0   ; TIME
      dc.b $90, $D, $80, $28,   $28   ; minutes : seconds
      dc.b $90, 1, $80, $2A, $48   ; :
      dc.b $90, 5, $80, $E0, $50   ; centiseconds
      dc.b $A0, $D, $80, 8, 0      ; RING
      dc.b $A0, 1, $80, 0, $20   ; S
      dc.b $A0, 9, $80, $30, $30   ; number of rings
      dc.b $40, 5, $81, $A, 0      ; lives icon
      dc.b $40, $D, $81, $E, $10   ; lives counter
      dc.b 0
byte_1C5F0:   dc.b $C
      dc.b $80, $D, $80, 0, 0      ; SCOR
      dc.b $80, $D, $80, $18,   $20   ; E + score left numbers
      dc.b $80, $D, $80, $20,   $40   ; score right numbers
      dc.b $90, $D, $80, $10,   0   ; TIME
      dc.b $90, $D, $80, $28,   $28   ; minutes : seconds
      dc.b $90, 1, $80, $2A, $48   ; :
      dc.b $90, 5, $80, $E0, $50   ; centiseconds
      dc.b $A0, $D, $A0, 8, 0      ; RING
      dc.b $A0, 1, $A0, 0, $20   ; S
      dc.b $A0, 9, $80, $30, $30   ; number of rings
      dc.b $40, 5, $81, $A, 0      ; lives icon
      dc.b $40, $D, $81, $E, $10   ; lives counter
      dc.b 0
byte_1C624:   dc.b $C
      dc.b $80, $D, $80, 0, 0      ; SCOR
      dc.b $80, $D, $80, $18,   $20   ; E + score left numbers
      dc.b $80, $D, $80, $20,   $40   ; score right numbers
      dc.b $90, $D, $A0, $10,   0   ; TIME
      dc.b $90, $D, $80, $28,   $28   ; minutes : seconds
      dc.b $90, 1, $80, $2A, $48   ; :
      dc.b $90, 5, $80, $E0, $50   ; centiseconds
      dc.b $A0, $D, $80, 8, 0      ; RING
      dc.b $A0, 1, $80, 0, $20   ; S
      dc.b $A0, 9, $80, $30, $30   ; number of rings
      dc.b $40, 5, $81, $A, 0      ; lives icon
      dc.b $40, $D, $81, $E, $10   ; lives counter
      dc.b 0
byte_1C658:   dc.b $C
      dc.b $80, $D, $80, 0, 0      ; SCOR
      dc.b $80, $D, $80, $18,   $20   ; E + score left numbers
      dc.b $80, $D, $80, $20,   $40   ; score right numbers
      dc.b $90, $D, $A0, $10,   0   ; TIME
      dc.b $90, $D, $80, $28,   $28   ; minutes : seconds
      dc.b $90, 1, $80, $2A, $48   ; :
      dc.b $90, 5, $80, $E0, $50   ; centiseconds
      dc.b $A0, $D, $A0, 8, 0      ; RING
      dc.b $A0, 1, $A0, 0, $20   ; S
      dc.b $A0, 9, $80, $30, $30   ; number of rings
      dc.b $40, 5, $81, $A, 0      ; lives icon
      dc.b $40, $D, $81, $E, $10   ; lives counter
      even

Was added the ":" and the "centiseconds" in each of 4 maps.

Very Nice!

To Fix the Frame Counter Bug, that because this tutorial is shown in start of each level, use this guide.
How to Fix the Frame Counter Bug

This bug is from ORIGINAL SONIC 1, and adding the Centiseconds you can see it in start of all levels.

After apply this guide How to Fix the Frame Counter Bug, we need correct the centiseconds when start from a lamppost.

Go to LevSz_ChkLamp, and between these two lines:

Code:

      jsr   Hud_Secs
      movem.l   (sp)+,d0-a6

Add this code:

Code:

      move.l   #$75400003,d0
      moveq   #0,d1
      move.b   ($FFFFFE25).w,d1 ; load   frames
      mulu.w   #$1AA,d1
      lsr.l   #8,d1
      jsr   Hud_Secs

To get a better effect when starting from a lamppost, to not always show the same time, go to Obj79_LoadInfo and comment or delete these lines:

Code:

      move.b   #59,($FFFFFE25).w
      subq.b   #1,($FFFFFE24).w

These lines say that the frame counter need be set to 59 and subtract 1 from seconds counter.


How work the centiseconds counter?

It work like the minutes counter and seconds counter, but have a difference, need convert the number of frames in number of centiseconds.

First a number is loaded, in this case the number of frames, after is converted to centiseconds (59 frames -> 99 centiseconds).

Second, the game get the correct art based on this number (centiseconds) and put it in VRAM, our case in F5C0 or tile number 7AE.

Third, the map use these tiles to show the centiseconds on screen, in this method is not being necessary decompress all the art in VRAM.

How the How to Fix the Frame Counter Bug was fixed, now this code is fixed too.

To download the ROM and the Source Code with these fixes, click here:
http://goo.gl/mpmgw

I know it's been forever since anybody's posted in this topic, but when I added the CentiSecond lines in sonic1.asm, it kept telling me "Error (1-- bytes) out of range". What am I doing wrong?

OMG! U SUX!!!

Just a joke.

What you could do, is open the main ASM file with E.N.A.E., and delete the two symbols that appear at the start.

Scott4 wrote:I know it's been forever since anybody's posted in this topic, but when I added the CentiSecond lines in sonic1.asm, it kept telling me "Error (1-- bytes) out of range". What am I doing wrong?

I think once you added this, you got that error.

Code:


CentiSecond:
      move.l  #$75400003,d0
      moveq  #0,d1
      move.b  ($FFFFFE25).w,d1 ; load  frames
      mulu.w  #$1AA,d1
      lsr.l  #8,d1
      jsr  Hud_Secs
      rts


It happened because of the TimeOver branch. In the branch where it said TimeOver, replace the command that's there with
jsr (Jump to SubRoutine) or jmp (JuMP). Either way, it should work, but if it doesn't work-- I can't help.

HackedSonic wrote:

Scott4 wrote:I know it's been forever since anybody's posted in this topic, but when I added the CentiSecond lines in sonic1.asm, it kept telling me "Error (1-- bytes) out of range". What am I doing wrong?

I think once you added this, you got that error.

Code:


CentiSecond:
      move.l  #$75400003,d0
      moveq  #0,d1
      move.b  ($FFFFFE25).w,d1 ; load  frames
      mulu.w  #$1AA,d1
      lsr.l  #8,d1
      jsr  Hud_Secs
      rts


It happened because of the TimeOver branch. In the branch where it said TimeOver, replace the command that's there with
jsr (Jump to SubRoutine) or jmp (JuMP). Either way, it should work, but if it doesn't work-- I can't help.

You know, this is Megamix stolen content. I mean this guide, and all guides by Ouricodoido.

Green Snake wrote:

HackedSonic wrote:

Scott4 wrote:I know it's been forever since anybody's posted in this topic, but when I added the CentiSecond lines in sonic1.asm, it kept telling me "Error (1-- bytes) out of range". What am I doing wrong?

I think once you added this, you got that error.

Code:


CentiSecond:
      move.l  #$75400003,d0
      moveq  #0,d1
      move.b  ($FFFFFE25).w,d1 ; load  frames
      mulu.w  #$1AA,d1
      lsr.l  #8,d1
      jsr  Hud_Secs
      rts


It happened because of the TimeOver branch. In the branch where it said TimeOver, replace the command that's there with
jsr (Jump to SubRoutine) or jmp (JuMP). Either way, it should work, but if it doesn't work-- I can't help.

You know, this is Megamix stolen content. I mean this guide, and all guides by Ouricodoido.

I checked the code from Megamix and it's different from this.

Compare homing attack codes. I see barely any difference

Just an annual year bump!