[Tool] Cheat Engine 設定

軟體：Cheat Engine
官網

功能：修改遊戲

用盡任何辦法都找不到值的解法，例：dolphin emulator

Edit -> Settings -> Scan Settings -> 勾選 MEM_MAPPED

值在 memory 中為 Big-Endian 表示
例：dolphin emulator 的值 256 在 memory 中表示為 01 00，但對於 CE 2Bytes 卻是 1 的值

第一種解法

可將 Value Type 改為 AOB（Array of byte) 解決，將會依 memory 順序尋找

第二種解法

新增 custom type

右鍵點選 Value Type 的下拉式選單
-> Define new custom type (Auto Assembler)
-> 將下面的程式碼依需求貼入視窗內
-> 按 OK
-> Value Type 下拉式選單可看到新增的 type (選擇後，可對此按右鍵進行編輯或刪除的動作）

2 Byte Big Endian

alloc(TypeName,256)
alloc(ByteSize,4)
alloc(ConvertRoutine,1024)
alloc(ConvertBackRoutine,1024)

TypeName:
db '2 Byte Big Endian',0

ByteSize:
dd 2

//The convert routine should hold a routine that converts the data to an integer (in eax)
//function declared as: stdcall int ConvertRoutine(unsigned char *input);
//Note: Keep in mind that this routine can be called by multiple threads at the same time.
ConvertRoutine:
//jmp dllname.functionname
[64-bit]
//or manual:
//parameters: (64-bit)
//rcx=address of input
xor eax,eax
mov ax,[rcx] //eax now contains the bytes 'input' pointed to
xchg ah,al //convert to big endian

ret
[/64-bit]

[32-bit]
//jmp dllname.functionname
//or manual:
//parameters: (32-bit)
push ebp
mov ebp,esp
//[ebp+8]=input
//example:
mov eax,[ebp+8] //place the address that contains the bytes into eax
mov ax,[eax] //place the bytes into eax so it's handled as a normal 4 byte value
and eax,ffff //cleanup
xchg ah,al //convert to big endian

pop ebp
ret 4
[/32-bit]

//The convert back routine should hold a routine that converts the given integer back to a row of bytes (e.g when the user wats to write a new value)
//function declared as: stdcall void ConvertBackRoutine(int i, unsigned char *output);
ConvertBackRoutine:
//jmp dllname.functionname
//or manual:
[64-bit]
//parameters: (64-bit)
//ecx=input
//rdx=address of output
//example:
xchg ch,cl //convert the little endian input into a big endian input
mov [rdx],cx //place the integer the 4 bytes pointed to by rdx

ret
[/64-bit]

[32-bit]
//parameters: (32-bit)
push ebp
mov ebp,esp
//[ebp+8]=input
//[ebp+c]=address of output
//example:
push eax
push ebx
mov eax,[ebp+8] //load the value into eax
mov ebx,[ebp+c] //load the address into ebx

//convert the value to big endian
xchg ah,al

mov [ebx],ax //write the value into the address
pop ebx
pop eax

pop ebp
ret 8
[/32-bit]

4 Byte Big Endian

alloc(TypeName,256)
alloc(ByteSize,4)
alloc(ConvertRoutine,1024)
alloc(ConvertBackRoutine,1024)

TypeName:
db '4 Byte Big Endian',0

ByteSize:
dd 4

//The convert routine should hold a routine that converts the data to an integer (in eax)
//function declared as: stdcall int ConvertRoutine(unsigned char *input);
//Note: Keep in mind that this routine can be called by multiple threads at the same time.
ConvertRoutine:
//jmp dllname.functionname
[64-bit]
//or manual:
//parameters: (64-bit)
//rcx=address of input
xor eax,eax
mov eax,[rcx] //eax now contains the bytes 'input' pointed to
bswap eax //convert to big endian

ret
[/64-bit]

[32-bit]
//jmp dllname.functionname
//or manual:
//parameters: (32-bit)
push ebp
mov ebp,esp
//[ebp+8]=input
//example:
mov eax,[ebp+8] //place the address that contains the bytes into eax
mov eax,[eax] //place the bytes into eax so it's handled as a normal 4 byte value

bswap eax

pop ebp
ret 4
[/32-bit]

//The convert back routine should hold a routine that converts the given integer back to a row of bytes (e.g when the user wats to write a new value)
//function declared as: stdcall void ConvertBackRoutine(int i, unsigned char *output);
ConvertBackRoutine:
//jmp dllname.functionname
//or manual:
[64-bit]
//parameters: (64-bit)
//ecx=input
//rdx=address of output
//example:
bswap ecx //convert the little endian input into a big endian input
mov [rdx],ecx //place the integer the 4 bytes pointed to by rdx

ret
[/64-bit]

[32-bit]
//parameters: (32-bit)
push ebp
mov ebp,esp
//[ebp+8]=input
//[ebp+c]=address of output
//example:
push eax
push ebx
mov eax,[ebp+8] //load the value into eax
mov ebx,[ebp+c] //load the address into ebx

//convert the value to big endian
bswap eax

mov [ebx],eax //write the value into the address
pop ebx
pop eax

pop ebp
ret 8
[/32-bit]

Float Big Endian

alloc(TypeName,256)
alloc(ByteSize,4)
alloc(ConvertRoutine,1024)
alloc(ConvertBackRoutine,1024)
alloc(UsesFloat,4)

TypeName:
db 'Float Big Endian',0
ByteSize:
dd 4
UsesFloat:
db 01

ConvertRoutine:
[32-bit]
push ebp
mov ebp,esp
mov eax,[ebp+8] //place the address that contains the bytes into eax
mov eax,[eax]   //place the bytes into eax
bswap eax
pop ebp
ret 4
[/32-bit]

[64-bit]
//rcx=address of input
mov eax,[rcx] //eax now contains the bytes 'input' pointed to
bswap eax
ret
[/64-bit]

ConvertBackRoutine:
[32-bit]
push ebp
mov ebp,esp
//[ebp+8]=input
//[ebp+c]=address of output
push eax
push ebx
mov eax,[ebp+8] //load the value into eax
mov ebx,[ebp+c] //load the address into ebx
bswap eax
mov [ebx],eax //write the value into the address
pop ebx
pop eax

pop ebp
ret 8
[/32-bit]

[64-bit]
//ecx=input
//rdx=address of output
bswap ecx
mov [rdx],ecx //place the integer the 4 bytes pointed to by rdx
ret
[/64-bit]

明明找到值，卻無法 freeze ，只要 freeze 立馬變問號的解法，例：dolphin emulator
但會影響部分遊戲的 AOB，需謹慎使用

Edit 
-> Settings 
-> Extra 
-> 勾選 Query memory region routines 和 Read/Write Process Memory

參考

Using Cheat Engine with Dolphin
Interpret value as Big-Endian?
Big Endian Float / Double
Problem with using Cheat Engine with Dolphin