This is a program I made to allow people ot make SX OS cheat codes easier. This does not require prior knowledge of the codetypes.
You can get cheat codes from: SX OS Cheats or Cheat Codes AMS and SX OS.
SX OS Cheat Hacker Guide
--[ 1. Introduction
This small guide attempts to shed some light on finding your own cheat codes for Switch games using the SX OS Cheat finder as well as detailing the specifics about the SX OS Cheat Code Format.
--[ 2. Address Space Layout Randomization
The Nintendo Switch Operating System (Horizon OS) implements Address Space Layout Randomization (from here on ASLR) for every process. What this means is that the absolute base address of for example a game's executable or a game's heap memory are not fixed in stone. SX OS does *not* disable this ASLR as it would effectively make your console less secure. The downside of this is that you as a cheat hunter will need to keep this in mind when finding cheats, but we've tried our best to encapsulate/hide these details at a high level.
When working with pointers in the SX OS Cheat Engine you can have three different type of pointers:
- * MAIN - memory addresses/pointers relative to the game's NSO executable
- * HEAP - memory addresses/pointers relative to the start of the game's heap
- * BASE - memory addresses/pointers that are neither part of MAIN/HEAP, they are displayed a relative to the address space base (usually 0x8000000)
Throughout the SX OS Cheat finder every memory address is thus displayed as: [MAIN+xxxx], [HEAP+xxxx], [BASE+xxxx]
When writing actual cheat codes you need to specify what kind of address you are reading/writing from, we support reading/writing from/to both MAIN and HEAP memory.
Remember that having cheat codes which write to a magic HEAP address are most of the time not very stable/reliable cheat codes, because the layout of the HEAP is not always fully deterministic and often times depends on how someone navigates through a game. In these cases it is better to study the game logic more and find pointers (or pointers to pointers, etc.) until you traced back to an address that resides in MAIN (a pointer in BSS or RO for example). At the end of this guide you will find a small case study of how the included codes for "Mega Man Legacy Collection" work.
--[ 3. SX OS Cheat Code Format
SX OS Cheat Codes are loosely inspired by older cheat engines such as Action Replay.
While old Action Replay cheat codes usually had a fixed width per code, some code types in the SX OS cheat engine can have a different length.
Cheat codes are placed inside the sxos folder on your microSD card. In order for SX OS to pick up your cheat codes they need to be correctly placed in the right subfolders. This subfolder format works like this: /sxos/titles/<titleID>/cheats/<buildID>.txt
Where titleID is the titleID of the game and buildID are the first 8bytes of the game's build ID formatted as ascii hexadecimals. Both the titleID and buildID for a running game are displayed below the SXOS logo when you navigate to the cheats tab in the SX OS Menu. The buildID is needed to properly deal with different versions of the same game, which might lead to incompatibilities for cheat codes.
When SX OS detects you have cheats on your SD cards for the currently running game but the buildID mismatches, it offers you to copy over the cheats from the other buildID to the one of the version you are currently running, if you want to experiment with (or fix) the compatibility of certain cheat codes.
A basic cheat code definition will look like this:
[Infinite Health]
11111111 22222222
11111111 22222222
11111111 22222222
Where 'Infinite Health' is the displayed name of the code and the lines containing '11111111 22222222' are all the codes that belong to this cheat.
The cheat engine supports up to 16 'scratch' registers which can be used for arbitrary purposes like stashing offsets or memory locations.
There is one special type of code. The "master code" which is not defined by enclosing the name in '[' and ']' but using '{' and '}' instead. The master code cannot be disabled and is executed before any other (enabled) cheat code. These exists to avoid duplication in multiple cheats which share certain characteristics.
An example of master code usage can be seen in the case study for the "Mega Man Legacy Collection" cheats you will find further down in this guide.
Below is an overview of the various code types currently implemented in the SX OS Cheat Engine.
# Code Type 0: Write to memory
0TMR00AA AAAAAAAA YYYYYYYY (YYYYYYYY)
T = width of write (1/2/4/8)
M = memory type (0 = main nso, 1 = heap)
R = register to be added as offset
A = address relative to (M)
With code type 0 you can do a write to memory.
# Code Type 1: Conditional statements
1TMC00AA AAAAAAAA YYYYYYYY (YYYYYYYY)
T = width of comparison value (1/2/4/8)
M = memory type (0 = main nso, 1 = heap)
C = Condition to use for comparison
A = Address relative to (M)
Y = Value to compare against
List of valid conditions:
- 1: Greater Than
- 2: Greater Than or Equal To
- 3: Lower Than
- 4: Lower Than or Equal To
- 5: Equal To
- 6: Not Equal To
# Code Type 2: End of conditional statement
20000000
This code type terminates an conditional block (Code type 3 or 😎
# Code Type 3: Looping
300R0000 VVVVVVVV
R = Register to use for loop counter
V = Loop count
310R0000
This code type is used at the end of the loop, use the same R value as for the start of the loop.
# Code Type 4: Load register with value
400R0000 VVVVVVVV VVVVVVVV
This code type will load one of the registers with a specific value
R = Register to be filled
V = Value to be put in register
# Code Type 5: Load register with value from memory
5TMRI0AA AAAAAAAA
T = Width of value to be loaded from memory (1/2/4/8)
M = memory type (0 = main nso, 1 = heap)
R = Load from register index
I = Load from register flag, set to 1 to load from register R instead of address A
A = Address relative to (M)
# Code Type 6: Store value to memory address from register
6T0RIor0 VVVVVVVV VVVVVVVV
T = Width of value to be stored to memory
R = Register index containing the memory address
I = Increment register flag, set to 1 to increment the register by T after storing
o = add additional offset from register 'r'
r = offset register index
V = value to be stored to memory
# Code Type 7: Apply arithmic operation to register
7T0RC000 VVVVVVVV
T = Width of value (1/2/4/8)
R = Register index to apply arithmic operation to
C = Arithmic operation to apply:
0 = addition, 1 = subtraction, 2 = multiplication, 3 = shift left, 4 = shift right
V = Value to be used during arithmic operation
# Code Type 8: Check for buttons being pressed
8kkkkkkk
k = keypad value to check against. the hex values for the various keys are:
0000001 - A
0000002 - B
0000004 - X
0000008 - Y
0000010 - Left Stick Pressed
0000020 - Right Stick Pressed
0000040 - L
0000080 - R
0000100 - ZL
0000200 - ZR
0000400 - Plus
0000800 - Minus
0001000 - Left
0002000 - Up
0004000 - Right
0008000 - Down
0010000 - Left Stick Left
0020000 - Left Stick Up
0040000 - Left Stick Right
0080000 - Left Stick Down
0100000 - Right Stick Left
0200000 - Right Stick Up
0400000 - Right Stick Right
0800000 - Right Stick Down
1000000 - SL
2000000 - SR
Multiple button values can be combined by OR'ing them together. For example A+B becomes 0000003, and A+B+X+Y becomes 000000f.
This code type otherwise behaves the same as the conditional code type 1.
--[ 4. Using the Cheat Finder in SX OS
SX OS Comes with a cheat searcher functionality that will help you in identifying the memory locations you need in order to write your own cheat codes. You start by launching a game, when you reach a point in the game where you want to start searching for cheats you hit the home button, and navigate to the album viewer (SX OS Menu).
You can start a cheat search by navigating to "Cheat Searcher" in the cheat tab of the SX OS menu. You will be prompted to pick what kind of value you want to start a cheat search for. If you dont know the answer you can try to approximate it. Lets say you want to hunt down the memory location of your in-game coins, and you know that you can accumulate over 1000 coins, you know for sure the data type you are looking for is gonna be bigger than 8-bit. This takes some experimentation and expertise to get used to.
Once you select the data type a memory dump for the running game will be created on your microSD card. This initial memory dump will take a while, it is advised to use a fast microSD card with enough free space. If you are looking for a specific/exact value, you can now select "Next Search" and pick "Exact Value", here you can enter the exact value you're looking for (in hexadecimal). Once the comparison is done it will tell you how many candidate memory locations it found and whether they are few enough to manually explore.
If there's too many candidates left, you simply exit the SX OS Rom Menu and go back to the game. Try to grab/lose some coins (or whatever item you're trying to cheat) and head back into the SX OS menu's cheat tab, pick "Next Search" and specify the condition. This can be "exact value" again if you know the value you're looking for, or simply "less than" if you know you just lost some of the desired item/stats. Keep iterating the searches until the cheat searcher tells you there's few enough candidate memory locations left for you to start exploring manually.
Manually exploring memory location candidates can be done by going to "View candidates" in the cheats menu. When you select a candidate from the list you will be brought to the builtin hex editor where you can change the values at these memory locations. Once you change a value you can go back to the game and see if your change had any/the desired effect to help in concluding whether you found the right memory location.
--[ 5. Case Study of "Mega Man: Legacy Collection" cheat codes.
Currently we only provide a single example of working cheat codes. We would love to spend all of our time on finding more cheats, but we have different priorities. 😉
The cheats we found are a slightly interesting example though of the various code types the SX OS Cheat Engine currently offers.
Mega Man: Legacy Collection is a collection of old Mega Man games originally released for the NES back in the day. The switch "port" of these games is actually a NES emulator in disguise. The meat of our Mega Man cheat codes hinges on the "master code" which finds the virtual NES' memory start address, from there we can apply any RAM patches to the NES memory as we wish. Let's have a look at how this works.
The full master code looks like this:
-- 8< ------------------------
{Master Code}
580f0000 00d3a2a0
580f1000 038cb840
580f1000 00000008
780f0000 0000000f
-- 8< ------------------------
The usage of '{' and '}' indicates that this is a master code, eg. a code that cannot be disabled and is always ran at the start of your cheat code list.
Lets break down the master code line by line:
580f0000 00d3a2a0
Code type 5 is 'Load register with value from memory', here we load a 8 byte (64bit) value, relative from MAIN (0) into register 'f' (15). The offset from the start of MAIN is 0xd3a2a0.
In pseudocode this would be something like:
register_f = read64(MAIN + 0xd3a2a0)
The next line reads:
580f1000 038cb840
This one is very similar to the first code, but notice how we have an '1' there. if you look this up in the SX OS Code Format description above you can see this is the 'Load from register flag'. If set to '1' we will take the address from the register specified in the register index field rather than a memory location relative from MAIN or HEAP. In pseudocode this would be:
register_f = read64(register_f + 0x38cb840)
The following line '580f1000 00000008' is more of the same, this time reading the next pointer from offset 8, or in pseudocode:
register_f = read64(register_f + 0x8)
Then finally we we end with '780f0000 0000000f'. Which uses code type 7 to do some basic arithmic to the memory location in register f. In pseudo code this would be:
register_f = register_f + 15
So in essence all the "master code" does is follow a bunch of pointers and eventually end up with a pointer in register F that holds the start of the virtual NES' memory. This register f value can then be used in any cheat codes that need to write/read from the virtual NES' memory in order to give Mega Man exciting super powers! 😉
Let's have a quick look at one of the game specific cheat codes for Mega Man 1:
[MM1 Infinite Health]
400e0000 00000000 0000006a
610f01e0 00000000 0000001c
The first line '400e0000 00000000 0000006a' is using code type #4 to load a register with a specific value. In this case we load register E with value 0x6a. 0x6a is the RAM offset for Mega Man's health.
The following line '610f01e0 00000000 0000001c' is using code type #6, which is "Store value to memory address from register" to write to this location.
Here we say write a 1 byte (8bit) value to the address: register_f + register_e.
The value to be written is 0x1c, the maximum value Mega Man's health can have in Mega Man 1.
--[ 6. Closing Words
We hope this guide outlines the possibilities of the cheat engine and the
need for decent master codes a bit. We are looking forward to many community
contributions with new cheat codes and of course suggestions for improving our
cheat code finder and engine.
Yours Sincerely, Team Xecuter -- Rocking the switch in 2018 and beyond!
Credits
- DarkFlare for the program and idea
- Team Xecuter for SX OS and codetypes