Development: Darthatron's Hacks

[mbcn10ww]

Here are some hacks that I have made for people. I hope you enjoy them. I have attempted to explain how they work as well, for those who want to learn. :)

Remove the "Previously on your quest..." scene from game load.

Spoiler:

Hack:

Change bytes at 110F44 to 00 20
Change bytes at 110F50 to C0 46

Explained:

Spoiler:

Original:

08110F32 loc_08110F32:                           @ CODE XREF: sub_08110F14+3Cj
08110F32                 MOVS    R0, R2
08110F34                 MULS    R0, R7
08110F36                 ADDS    R0, R5, R0
08110F38                 ADDS    R0, R0, R6
08110F3A                 LDRB    R0, [R0]
08110F3C                 LDR     R3, =unk_0203ADF9
08110F3E                 CMP     R0, #0
08110F40                 BEQ     loc_08110F48
08110F42                 LDRB    R0, [R1]
[S-HIGHLIGHT]08110F44                 ADDS    R0, #1[/S-HIGHLIGHT]
08110F46                 STRB    R0, [R1]
08110F48
08110F48 loc_08110F48:                           @ CODE XREF: sub_08110F14+2Cj
08110F48                 ADDS    R0, R2, #1
08110F4A                 LSLS    R0, R0, #0x18
08110F4C                 LSRS    R2, R0, #0x18
08110F4E                 CMP     R2, #3
[S-HIGHLIGHT]08110F50                 BLS     loc_08110F32[/S-HIGHLIGHT]

Basically, this code counts the amount of important events that have occured. Once it reaches 3 (CMP R2, #3), it stops counting and continues the game as normal. What we want to do is make it so it always returns zero. We do this by setting R0 to 0 instead of incrementing as normal, and then removing the loop with the NOP (which literally does nothing) command.

New:

08110F32 loc_08110F32:                           @ CODE XREF: sub_08110F14+3Cj
08110F32                 MOVS    R0, R2
08110F34                 MULS    R0, R7
08110F36                 ADDS    R0, R5, R0
08110F38                 ADDS    R0, R0, R6
08110F3A                 LDRB    R0, [R0]
08110F3C                 LDR     R3, =unk_0203ADF9
08110F3E                 CMP     R0, #0
08110F40                 BEQ     loc_08110F48
08110F42                 LDRB    R0, [R1]
[S-HIGHLIGHT]08110F44                 MOV     R0, #0[/S-HIGHLIGHT]
08110F46                 STRB    R0, [R1]
08110F48
08110F48 loc_08110F48:                           @ CODE XREF: sub_08110F14+2Cj
08110F48                 ADDS    R0, R2, #1
08110F4A                 LSLS    R0, R0, #0x18
08110F4C                 LSRS    R2, R0, #0x18
08110F4E                 CMP     R2, #3
[S-HIGHLIGHT]08110F50                 NOP[/S-HIGHLIGHT]

Run a script from an items "Use" command or from registering it from select...

Spoiler:

First of all, follow DavidJCobb's Item Creation Tutorial, until the part where it attempts to add scripts, to actually create a new item. But change the "Type" combobox to #2 in the Item Manager. JPANs engine is not required!

Next step is to put this (assmelbed) code somewhere:

10 B5 04 1C 78 46 13 30 0C 49 08 60 20 1C 0C 49 00 F0 10 F8 10 BC 01 BC 00 47 10 B5 04 1C 0A 48 05 49 00 F0 07 F8 20 1C 06 49 00 F0 03 F8 10 BC 01 BC 00 47 08 47 C0 46 E5 9A 06 08 98 99 03 02 3D 10 0A 08 09 75 07 08 XX XX XX 08

Where XXXXXX is the location of your script reversed. 800300 would be 00 03 80, for example.

By entering this hex somewhere in the ROM and putting it's offset+1 in the "Field Usage" box in the Item Manager, you can call any script by using the item from the bag or by select. :) Say I put the routine at 800000 in the ROM, the Field Usage box would be 08800001.
Here's the unassembled code:

Spoiler:

.text
.align 2
.thumb
.thumb_func
.global Hax
	
setup:
	push {r4, lr}
	mov r4, r0
	mov r0, pc
	add r0, #0x13
	ldr r1, .unk_02039998
	str r0, [r1]
	mov r0, r4
	ldr r1, .sub_080A103C
	bl bx_r1
	pop {r4}
	pop {r0}
	bx r0

main:
	push {r4, lr}
	mov r4, r0
	ldr r0, .ScriptToCall
	ldr r1, .CallScript
	bl bx_r1
	mov r0, r4
	ldr r1, .del_c3_from_linked_list
	bl bx_r1
	pop {r4}
	pop {r0}
	bx r0

.align 2
bx_r1:
	bx r1

.align 2
.CallScript:
	.word 0x08069AE4+1
.unk_02039998:
	.word 0x02039998
.sub_080A103C:
	.word 0x080A103C+1
.del_c3_from_linked_list:
	.word 0x08077508+1
.ScriptToCall:
	.word 0x08800300

More to come as I can be bothered.

EDIT: Also feel free to ask about/request stuff here. I may not do all requests, but I'll try my best. :)

Hey dude, if I want to make it work with an option on the START Menu, what I need to change on that routine? I need to call a multichoice box with an option of the START Menu.

 

[Squeetz]

Run a script from an items "Use" command or from registering it from select...

While this is better than JPAN's method (due to his not working with Select or in the Berry Pouch), the script offset is static, so you would have to use a separate routine for each item you wanted to use.
I added a bit at the end that takes the script pointer from the last 4 bytes in the item data (aka the "Extra" field in G3T) just like JPAN's routine.

Routine:

Spoiler:

.thumb
.global itemrunscript

setup:
push {r4, lr}
mov r4, r0
mov r0, pc
add r0, #0x13
ldr r1, run_eventually
str r0, [r1]
mov r0, r4
ldr r1, run_eventually_start
bl linker
pop {r4}
pop {r0}
bx r0
main:
push {r4, lr}
mov r4, r0
ldr r0, var_800E @last used item
ldrh r0, [r0]
mov r1, #0x2C @item entry length
mul r0, r1
ldr r1, item_extra @last 4 bytes of item entry 0
add r0, r0, r1
ldr r0, [r0]
ldr r1, script_start
bl linker
mov r0, r4
ldr r1, task_del
bl linker
pop {r4}
pop {r0}
bx r0

linker:
bx r1

.align 2
run_eventually: .word 0x02039998
run_eventually_start: .word 0x080A103C|1
script_start: .word 0x08069AE4|1
task_del: .word 0x08077508|1
var_800E: .word 0x0203AD30
item_extra: .word 0x083DB050

 

[AtecainCorp.]

I have huge problems with this hack. Every time when i set by this script something to work. My game freeze. I adding to main script in ASM +1 where i put link to script. But why game freeze?

 

[Spherical Ice]

I have huge problems with this hack. Every time when i set by this script something to work. My game freeze. I adding to main script in ASM +1 where i put link to script. But why game freeze?

This is for FireRed, not Ruby.

 

[AtecainCorp.]

This is for FireRed, not Ruby.

But someone put here RUBY port of this hack. And even with that port things do not work. In my case is script for Reveal Mirror since I've make formes of "Forces of Nature"

 

[Lunos]

I tested it (on emerald) and it works

I know it's been a lot of time since that post, but I remembered it and decided to come and ask for help.
I don't quite understand what exactly is failing.

What I'm trying to do is to attach jiangzhengwenjz's EV/IV Screen for Emerald onto my Theta Emerald EX ROM for personal use.
I inserted the routine from the main post at E1ABB0
Changed "XX XX XX" to "EF 04 80" since 8004EF is where I've inserted the script that would allow me to activate the EV/IV Screen.
I already configured the Item that I want to use for this accordingly too (Index 34 because it comes after the Green Shard, Use-of-SELECT and the field usage on Item Manager is "8E1ABB1").
I left all the files from jiang's code by default, so the callasm 0x8F90001 should work perfectly on my ROM.
This is the script I've attached to the item
And finally, this is the result:

Halp..? ;_; ....

EDIT: Fixed, Phenom's routine does work.

 

[dearman4]

Having some trouble with this in emerald, I am trying to have an item set or clear a flag (200) but I either get a black screen or the item is selected with no message and the cursor is locked until B is pressed, with the flag not being set or cleared. I have Phenom's routine inserted at 0xE446D0 with the script I am trying to run at 0xE44512 so the pointer is 12 45 E4 and using the Complete Item Editor I have the item (Exp. Share if that matters) Type set to Use-of-SELECT and Use set to 01 Anywhere, in the Script Item section, ScriptOffset at 08E44512, and ASM offset at 08E446D0. Is there something I am doing wrong?