Configuration Memory

ARM11 Kernel Configuration Memory

NAME	PROCESS VIRTUAL ADDRESS	WIDTH
KERNEL_?	0x1FF80000	1
KERNEL_VERSIONREVISION	0x1FF80001	1
KERNEL_VERSIONMINOR	0x1FF80002	1
KERNEL_VERSIONMAJOR	0x1FF80003	1
UPDATEFLAG	0x1FF80004	4
NSTID	0x1FF80008	8
SYSCOREVER	0x1FF80010	4
ENVINFO	0x1FF80014	1
UNITINFO	0x1FF80015	1
PREV_FIRM	0x1FF80016	1
KERNEL_CTRSDKVERSION	0x1FF80018	4
APPMEMTYPE	0x1FF80030	4
APPMEMALLOC	0x1FF80040	4
SYSMEMALLOC	0x1FF80044	4
BASEMEMALLOC	0x1FF80048	4
FIRM_?	0x1FF80060	1
FIRM_VERSIONREVISION	0x1FF80061	1
FIRM_VERSIONMINOR	0x1FF80062	1
FIRM_VERSIONMAJOR	0x1FF80063	1
FIRM_SYSCOREVER	0x1FF80064	4
FIRM_CTRSDKVERSION	0x1FF80068	4

This memory page is read-only for ARM11 processes. This memory and the kernel code for it only exists under NATIVE_FIRM/SAFE_MODE_FIRM.

The FIRM_* fields are by default identical to the KERNEL_* fields. However, the FIRM_* fields can be overridden via FIRM-launch parameters, see here.

Besides mem-region related fields, the data written here by the old 3DS/new 3DS kernels is identical.

Shared Memory Page For ARM11 Processes

NAME	PROCESS VIRTUAL ADDRESS	WIDTH
bit0 selects DATETIME_0 or DATETIME_1.	0x1FF81000	4
RUNNING_HW (1=product, 2=devboard, 3=debugger, 4=capture)	0x1FF81004	1
MCU_HW_INFO	0x1FF81005	1
DATETIME_0 {(u64)MillisecondsSinceFirstJan1900,(u64)SystemTickLastTimeThisWasUpdated,(u32)unk,(u32)unk,(u32)unk,(u32)unk}	0x1FF81020	32
DATETIME_1	0x1FF81040	32
WIFI_MACADDR	0x1FF81060	6
WIFI_LINKLEVEL Ranges from 0-3; 0 stands for no or a poor network connection; 3 stands for a good connection. This corresponds with the number of wifi bars displayed by Home Menu.	0x1FF81066	1
WIFI_? Likely wifi hardware related, NWM module initializes this. Regular Old3DS value = 0x00, regular New3DS value = 0x02.	0x1FF81067	1
3D_SLIDERSTATE	0x1FF81080	4
3D_LEDSTATE	0x1FF81084	1
BATTERY_LEDSTATE	0x1FF81085	1
On startup, and under certain conditions, NS will continuously call svcSleepThread(1000*1000) as long as bit0 of this field is clear. ptmInitialize() sets this after writing MCU unit info to sharedmem.	0x1FF81086	1
MENUTID	0x1FF810A0	8
ACTIVEMENUTID	0x1FF810A8	8
Signed? Headsets connected?	0x1FF810C0	1

This memory page is normally read-only for ARM11 processes, write-access is determined by the process exheader kernel "shared page writing" flag. This memory only exists under NATIVE_FIRM/SAFE_MODE_FIRM.

ARM11 Kernel Config Fields

0x1FF80000 / 0x1FF80060

Unknown, this is normally value 0.

KERNEL_VERSIONREVISION / FIRM_VERSIONREVISION

This is the version-revision for the currently running FIRM.

KERNEL_VERSIONMINOR

This is the version-minor from ((title-version & 0x3FF) >> 4), for the currently running FIRM. The values from KERNEL_VERSIONMINOR and KERNEL_VERSIONMAJOR can be stored in applications' CXI exheader.

FIRM_VERSIONMINOR

This is the same as KERNEL_VERSIONMINOR. After AM:InstallNATIVEFIRM checks FIRM_SYSCOREVER, AM:InstallNATIVEFIRM then compares FIRM_VERSIONMINOR with the NATIVE_FIRM ((title-version & 0x3FF) >> 4), when the latter is larger than FIRM_VERSIONMINOR AM:InstallNATIVEFIRM will trigger a FIRM install.

KERNEL_VERSIONMAJOR / FIRM_VERSIONMAJOR

This is the version-major for the currently running FIRM.

UPDATEFLAG

Normally this flag is zero. When the ARM11 kernel is booting on non-factory FIRM it will set this flag to 1, when bit0 from the data which field 0x1FF80016 is loaded from is clear, if the following PAD buttons are pressed: L, R, A, Up. When this flag is set, NS will launch the System Updater title instead of Home Menu.

NSTID

This field contains the titleID of the first title to launch from CTR-NAND after the FIRM system processes are loaded. The PM module launches this title. If this field titleID is all-zero, the system will not attempt to launch the title. The regular ARM11 kernel sets this to the regular NS titleID, while the SAFE_MODE ARM11 kernel sets this to the SAFE_MODE NS titleID. The factory FIRM ARM11-kernel sets this to the NS TID from here.

SYSCOREVER

This field is initialized by the ARM11 kernel, this is the programID-low of the running FIRM. When launching CXIs, the value stored here must match the core version field stored in the CXI exheader. If they do not match, the PM module will refuse to launch the ARM11 process.

With factory NATIVE_FIRM, this is set to 0x0, even though the FIRM programID-low is 0x2. However, the factory system-titles have core-version set to 0x2. Hence, this config-mem SYSCOREVER field might not be used by factory system processes?

FIRM_SYSCOREVER

Normally this is the same as SYSCOREVER. This used by AM:InstallNATIVEFIRM for comparing with the NATIVE_FIRM titleID-low. When the low u8 from the NATIVE_FIRM titleID-low is larger than FIRMSYSCOREVER, AM:InstallNATIVEFIRM will trigger FIRM installing. When that u8 is not larger than FIRM_SYSCOREVER, and these two values don't match, AM:InstallNATIVEFIRM will return an error.

ENVINFO

Bit	Description
0	Clear for developer unit, set for retail.(See 0x1FF80015)
1	IsJtagConnected
2-7	?

Bit1 in this field is set by the ARM11 kernel when ARM debug CP14 DSCR bit14 is set (halting debug-mode enabled). NS loads the menu TID from MENUTID when bits 1-7 of this field are clear. ErrDisp will display development error info when bit0 is clear.

UNITINFO

Value	Boot Env
0	Prod
1	Dev
2	Debugger
3	Firm

The ARM11 loads the value of CFG_UNITINFO from 0x1FFFFFF0+1 during startup, which is written by the ARM9 during ARM9<>ARM11 kernel sync.

When this field is zero, bit0 for ENVINFO is set for retail. When this field is non-zero, bit0 for ENVINFO is clear for dev/debug units, and an ARM11 kernel state flag which enables debugging is set. JTAG is only enabled for debugger and "firm" modes (bit1).

PREV_FIRM

Value	Description
0	Cold Boot
1	Reset from CTR mode
3	Reset from TWL mode
5	Reset from NTR mode
7	Reset from AGB mode

The ARM11 loads this value from 0x1FFFFFF0+2 during startup, which is written by the ARM9 during ARM9<>ARM11 kernel sync.

This originates from the low 8-bits of register 0x10010000. When bit0 is set, the ARM11 kernel will not set the UPDATEFLAG to value 1.

KERNEL_CTRSDKVERSION / FIRM_CTRSDKVERSION

This is the CTR-SDK version which was used to build the currently running FIRM.

APPMEMTYPE

The value of this field determines the size for APPMEMALLOC. The retail type(value0) is used when the type is not values 2-5. See Memory_layout for the table of values for this and the mem-region sizes.

APPMEMALLOC

This contains the total size of the memory that can be allocated with the APPLICATION memory-region, see here.

SYSMEMALLOC

Same as APPMEMALLOC except for the SYSTEM mem-region, see here.

BASEMEMALLOC

Same as APPMEMALLOC except for the BASE mem-region, see here.

Shared Memory Page Fields

WIFI_MACADDR

This is the WiFi MAC address for the 3DS. This is initialized by the NWM module, it's unknown where the MAC address written here was originally loaded from.

3D_SLIDERSTATE

This float contains the state of the 3D slider. The range of this float is value 0.0f for "off", and 1.0f for max.

This is written/updated by HID module.

3D_LEDSTATE

When non-zero, the 3D LED is disabled. See GSPGPU:SetLedForceOff.

MENUTID

Unknown, contains the menu TID (used by NS)

ACTIVEMENUTID

This contains the titleID of the currently running menu launched by NS.

NATIVE_FIRM Versions

See FIRM.