Basic Questions and Answers Thread

It depends how you want to implement it. If you want when you once collect it it stays and you cant collect it more, then what Calvin suggested is a working method. If you want to lose the emeralds, you could save a variable at beginning of the level of how many emeralds you had, and if you die, the amount you currently have would be reset to the value in this variable

 

Hello, where is the routine of when Sonic restart the level after he dies?
I don't find it.

 

EDIT -- Delete this post as it is no longer needed.

 

You're probably over thinking this. Where did you already check? The answer is much easier to search for and find than you probably think, especially if you're using the Git disassembly (this is for Sonic 1 right?). I'll give a hint though; there is a flag that is set that controls whether the level is due to restart. Try checking where it gets used in the existing game. Good Luck!

 

Fixed. Thank you anyway.

 

Even after googleing the question I had before I was unable to figure out how to add the variable. What I am trying to do is have the end of act subroutine update a variable(That I am still unsure of how to make) with the number of emeralds you have successfully obtained without dying in that level and have the game start with that amount next level and still retain that after you died in the next level.

If you are replying to me learn asm. (I am) I just don't understand every single part of it. I understand what some of the commands do but not all of them. The only way for me to learn is to find a resource that lets me learn. And because I could not find one that worked for me I am asking for help so I can learn and not so I can just rip the code and go on with my day without learning something. If someone has a resource that could help me learn about the thing I am trying to learn above please respond with it because I could not find one on google or in MarkeyJester's asm guide that would help me with what I need help with.

 

Everyone here repeated to me: Learn about ASM.
I think it also applies to you?

 

Why not just, I dunno, look at how all the other variables are defined?

 

I tried to none of the variables that I could fine have a pattern that I could understand how they are formed or edited.

 

It's much simpler than you might think (I honestly over thought this myself, when I figured it out). Looking at the existing variable list (in the file variables.asm, for Git Sonic 1), just do as the other ones do, but simply use a name that's unique (v_something), and equate it to an unused ram address (if you search on these forums, there's a post that lists every unused ram address). That's it! Then be sure to leave a comment to the right of the semicolon so you remember what it does, or what it's for. I suggest looking up why you should be careful with odd numbered addresses though, as hardware doesn't like those sometimes.

 

I found a way that might work without the use of variables but it is currently not working. I will attach the rom below because I cannot explain in words what is happening. In the rom when you collect the emerald monitors and die it resets to zero. After resetting to zero collect the emerald monitors again and kill sonic they will change to a weird value. I edited the killsonic subroutine to subtract the emeralds collected in that level. The emeralds address is now being used to count the emeralds collected in that level and is supposed to clear at death and going to the next level.


Kill sonic

Code:

; ---------------------------------------------------------------------------
; Subroutine to    kill Sonic
; ---------------------------------------------------------------------------

; ||||||||||||||| S U B    R O U T    I N E |||||||||||||||||||||||||||||||||||||||


KillSonic:
        tst.w    ($FFFFFE08).w    ; is debug mode    active?
        bne.w    Kill_NoDeath    ; if yes, branch
        move.b    #0,($FFFFFE2D).w ; remove invincibility
        move.b    #6,$24(a0)
        bsr.w    Sonic_ResetOnFloor
        bset    #1,$22(a0)
        move.w    #-$700,$12(a0)
        move.w    #0,$10(a0)
        move.w    #0,$14(a0)
        move.w    $C(a0),$38(a0)
        move.b    #$18,$1C(a0)
        bset    #7,2(a0)
        cmpi.b    #7,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald7death    ; if yes, branch
        cmpi.b    #6,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald6death    ; if yes, branch
        cmpi.b    #5,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald5death    ; if yes, branch
        cmpi.b    #4,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald4death    ; if yes, branch
        cmpi.b    #3,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald3death    ; if yes, branch
        cmpi.b    #2,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald2death    ; if yes, branch
        cmpi.b    #1,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald1death    ; if yes, branch
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        
emerald7death:
        subq.b    #7,($FFFFFE12).w
        subq.b    #7,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds
emerald6death:
        subq.b    #6,($FFFFFE12).w
        subq.b    #6,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds       
emerald5death:
        subq.b    #5,($FFFFFE12).w
        subq.b    #5,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds
emerald4death:
        subq.b    #4,($FFFFFE12).w
        subq.b    #4,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds
emerald3death:
        subq.b    #3,($FFFFFE12).w
        subq.b    #3,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds
emerald2death:
        subq.b    #2,($FFFFFE12).w
        subq.b    #2,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds
emerald1death:
        subq.b    #1,($FFFFFE12).w
        subq.b    #1,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds

Kill_Sound:
        jsr    (PlaySound_Special).l
        

Kill_NoDeath:
        moveq    #-1,d0
        rts   
; End of function KillSonic

emerald monitor code

Code:

Obj2E_ChkSonic:
        cmpi.b    #2,d0        ; does monitor contain Sonic?
        bne.s    Obj2E_ChkShoes
        addi.b    #1,($FFFFFE57).w ; do you have all emeralds?
        jmp    Obj09_Get1Up

ExtraLife:
        addq.b    #1,($FFFFFE12).w ; add 1 to the    number of lives    you have
        addq.b    #1,($FFFFFE1C).w ; add 1 to the    lives counter
        move.w    #$88,d0
        jmp    (PlaySound).l    ; play extra life music
; ===========================================================================

 

It probably has something to do with the fact your code doesn't use branches to exit the little if/else chain you have going on.

 

How should I make it exit with branches because I am unsure of how it would help it?

 

Code:

emerald7death:
       subq.b    #7,($FFFFFE12).w
        subq.b    #7,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds
emerald6death:
        subq.b    #6,($FFFFFE12).w
        subq.b    #6,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    #0,($FFFFFE57).w ; clear emeralds

One of the most basic concepts in programming: the instructions are executed from top to bottom, that is, unless something changes where the CPU looks for code. Branch instructions do that. Can you seriously not see how the code after emerald6death would start executing as soon as emerald7death's instructions as done?

 

I tried that with an rts wouldn't it return to start of the routine and do the same job?

 

Branch instruction.

 

I branched it it and it stops working after 1 clear. Am I doing something wrong.

Code:

KillSonic:
        tst.w    ($FFFFFE08).w    ; is debug mode    active?
        bne.w    Kill_NoDeath    ; if yes, branch
        move.b    #0,($FFFFFE2D).w ; remove invincibility
        move.b    #6,$24(a0)
        bsr.w    Sonic_ResetOnFloor
        bset    #1,$22(a0)
        move.w    #-$700,$12(a0)
        move.w    #0,$10(a0)
        move.w    #0,$14(a0)
        move.w    $C(a0),$38(a0)
        move.b    #$18,$1C(a0)
        bset    #7,2(a0)
        cmpi.b    #7,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald7death    ; if yes, branch
        cmpi.b    #6,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald6death    ; if yes, branch
        cmpi.b    #5,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald5death    ; if yes, branch
        cmpi.b    #4,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald4death    ; if yes, branch
        cmpi.b    #3,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald3death    ; if yes, branch
        cmpi.b    #2,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald2death    ; if yes, branch
        cmpi.b    #1,($FFFFFE57).w ; do you have all emeralds?
        beq.w    emerald1death    ; if yes, branch
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        jmp        touch_special
        
emerald7death:
        subq.b    #7,($FFFFFE12).w
        subq.b    #7,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special
emerald6death:
        subq.b    #6,($FFFFFE12).w
        subq.b    #6,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special
emerald5death:
        subq.b    #5,($FFFFFE12).w
        subq.b    #5,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special
emerald4death:
        subq.b    #4,($FFFFFE12).w
        subq.b    #4,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special
emerald3death:
        subq.b    #3,($FFFFFE12).w
        subq.b    #3,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special
emerald2death:
        subq.b    #2,($FFFFFE12).w
        subq.b    #2,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special
emerald1death:
        subq.b    #1,($FFFFFE12).w
        subq.b    #1,($FFFFFE1C).w
        move.w    #$A3,d0        ; play normal death sound
        cmpi.b    #$36,(a2)    ; check    if you were killed by spikes
        bne.w    Kill_Sound
        move.w    #$A6,d0        ; play spikes death sound
        move.b    d0,($FFFFFE57).w ; clear emeralds
        move.l    d0,($FFFFFE58).w ; clear emeralds
        move.l    d0,($FFFFFE5C).w ; clear emeralds
        tst.w    ($FFFFFE57).w
        bra.w    touch_special

Kill_Sound:
        jsr    (PlaySound_Special).l
        

Kill_NoDeath:
        moveq    #-1,d0
        rts   
; End of function KillSonic

 

...I see you're 'clearing' the emeralds with the value '$A6'. That's probably meant to be a 0. Also, aren't you meant to be branching to Kill_Sound instead of touch_special?

 

I branched it back to killsound is there something better I should be doing like clearing it to a different value.

Edit: I got it to work for the most part thanks Clownacy and Calvin.

EDIT2: Never mind when I die with Zero emeralds the counter I assume is trying to go into the negatives. What can I do???