Joy-Con

Joy-Con is the name for the Switch's primary game controllers. The controllers communicate to the console through bluetooth and can be disconnected from the main unit.

Hardware

The controllers themselves are simple to disassemble and identify.

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The front of the Joy-Con internal[1]

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The rear of the Joy-Con internal[2]

Color	Item
Red	Broadcom BCM20734 Bluetooth 4.1/2.4 GHz Transceiver
Orange	STMicroelectronics NFCBEA 812006 33 (Likely NFC reader IC)
Yellow	Macronix International MX25U4033E 4 Mb CMOS Flash

Firmware

See also: Joy-Con Firmware

The firmware of the Joy-Cons seems to be generic across all instances. Details such as the handedness of the controller and the color is just indicated in a configuration part of the flash. Judging by quick glance at the firmware, it's probably identical to that used on the Pro Controller as well.

Controller	1.0.0
Joy-Con Left (Blue)	flash dump
Joy-Con Right (Red)	flash dump

The flash is in a patch-ram format. Tools for dealing with it are available [3]. A dump of the ROM region (taken while firmware was running) can be found here. Note this is the same SoC used on the other controller models, as well.

Bluetooth HID

Commands

Command	Name
0x00
0x01	PairingOut
0x02	GetDeviceInfo
0x03	SetDataFormat
0x04	LRButtonDetection
0x05	Page
0x06	Reset
0x07	ClearPairingInfo
0x08	Shipment
0x10	SerialFlashRead
0x11	SerialFlashWrite
0x12	SerialFlashSectorErase
0x20	McuReset
0x21	McuWrite
0x22	McuResume
0x23
0x24	McuPollingEnable
0x25	McuPollingDisable
0x28	AttachmentWrite
0x29
0x2A	AttachmentEnable
0x2B
0x30	SetIndicatorLed
0x31	GetIndicatorLed
0x38	SetNotificationLed
0x40	SensorSleep
0x41	SensorConfig
0x42	SensorWrite
0x43	SensorRead
0x48	MotorEnable
0x50	GetBatteryVoltage
0x51	WriteChargeSetting
0x52
0x58	ExtDevWrite
0x59	GetExtDevInfo
0x5A	ExtDevPollingEnable
0x5B	ExtDevPollingDisable
0x5C	ExtDevInFormatConfig
0x60	InternalAttachmentWrite
0x61
0x62	InternalAttachmentEnable
0x63	InternalAttachmentPollingEnable
0x64	InternalAttachmentPollingDisable
0x80	Ack
0x81	PairingIn
0x82	DeviceInfo
0x83	LRButtonElapsedTime
0x90	SerialFlashData
0xA0	McuData
0xA8	AttachmentData
0xAA	InternalAttachmentRead
0xB0	IndicatorLed
0xC0	SensorData
0xD0	BatteryVoltage
0xD8	ExtDevRead
0xD9	ExtDevInfo

Left & Right Separate Joy-con

When paired directly to a computer over bluetooth, the joy-con both provide identical HID input report descriptor. This does not appear to include motion controls, IR data, or NFC. They both behave as detached single-player controllers.

HID Input Report Descriptor (Hexadecimal):

00000000: 05010905 A1010601 FF852109 21750895  ....¡...ÿ…!.!u.•
00000010: 30810285 30093075 08953081 02853109  0..…0.0u.•0..…1.
00000020: 31750896 69018102 85320932 75089669  1u.–i...…2.2u.–i
00000030: 01810285 33093375 08966901 8102853F  ...…3.3u.–i...…?
00000040: 05091901 29101500 25017501 95108102  ....)...%.u.•...
00000050: 05010939 15002507 75049501 81420509  ...9..%.u.•..B..
00000060: 75049501 81010501 09300931 09330934  u.•......0.1.3.4
00000070: 16000027 FFFF0000 75109504 81020601  ...'ÿÿ..u.•.....
00000080: FF850109 01750895 30910285 10091075  ÿ…...u.•0‘.…...u
00000090: 08953091 02851109 11750895 30910285  .•0‘.…...u.•0‘.…
000000A0: 12091275 08953091 02C0               ...u.•0‘.À

Parsed Bytes	Description
0x05, 0x01,	Usage Page (Generic Desktop Ctrls)
0x09, 0x05,	Usage (Game Pad)
0xA1, 0x01,	Collection (Application)
0x06, 0x01, 0xFF,	Usage Page (Vendor Defined 0xFF01)
0x85, 0x21,	Report ID (33)
0x09, 0x21,	Usage (0x21)
0x75, 0x08,	Report Size (8)
0x95, 0x30,	Report Count (48)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x85, 0x30,	Report ID (48)
0x09, 0x30,	Usage (0x30)
0x75, 0x08,	Report Size (8)
0x95, 0x30,	Report Count (48)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x85, 0x31,	Report ID (49)
0x09, 0x31,	Usage (0x31)
0x75, 0x08,	Report Size (8)
0x96, 0x69, 0x01,	Report Count (361)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x85, 0x32,	Report ID (50)
0x09, 0x32,	Usage (0x32)
0x75, 0x08,	Report Size (8)
0x96, 0x69, 0x01,	Report Count (361)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x85, 0x33,	Report ID (51)
0x09, 0x33,	Usage (0x33)
0x75, 0x08,	Report Size (8)
0x96, 0x69, 0x01,	Report Count (361)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x85, 0x3F,	Report ID (63)
0x05, 0x09,	Usage Page (Button)
0x19, 0x01,	Usage Minimum (0x01)
0x29, 0x10,	Usage Maximum (0x10)
0x15, 0x00,	Logical Minimum (0)
0x25, 0x01,	Logical Maximum (1)
0x75, 0x01,	Report Size (1)
0x95, 0x10,	Report Count (16)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x05, 0x01,	Usage Page (Generic Desktop Ctrls)
0x09, 0x39,	Usage (Hat switch)
0x15, 0x00,	Logical Minimum (0)
0x25, 0x07,	Logical Maximum (7)
0x75, 0x04,	Report Size (4)
0x95, 0x01,	Report Count (1)
0x81, 0x42,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,Null State)
0x05, 0x09,	Usage Page (Button)
0x75, 0x04,	Report Size (4)
0x95, 0x01,	Report Count (1)
0x81, 0x01,	Input (Const,Array,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x05, 0x01,	Usage Page (Generic Desktop Ctrls)
0x09, 0x30,	Usage (X)
0x09, 0x31,	Usage (Y)
0x09, 0x33,	Usage (Rx)
0x09, 0x34,	Usage (Ry)
0x16, 0x00, 0x00,	Logical Minimum (0)
0x27, 0xFF, 0xFF, 0x00, 0x00,	Logical Maximum (65534)
0x75, 0x10,	Report Size (16)
0x95, 0x04,	Report Count (4)
0x81, 0x02,	Input (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position)
0x06, 0x01, 0xFF,	Usage Page (Vendor Defined 0xFF01)
0x85, 0x01,	Report ID (1)
0x09, 0x01,	Usage (0x01)
0x75, 0x08,	Report Size (8)
0x95, 0x30,	Report Count (48)
0x91, 0x02,	Output (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position,Non-volatile)
0x85, 0x10,	Report ID (16)
0x09, 0x10,	Usage (0x10)
0x75, 0x08,	Report Size (8)
0x95, 0x30,	Report Count (48)
0x91, 0x02,	Output (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position,Non-volatile)
0x85, 0x11,	Report ID (17)
0x09, 0x11,	Usage (0x11)
0x75, 0x08,	Report Size (8)
0x95, 0x30,	Report Count (48)
0x91, 0x02,	Output (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position,Non-volatile)
0x85, 0x12,	Report ID (18)
0x09, 0x12,	Usage (0x12)
0x75, 0x08,	Report Size (8)
0x95, 0x30,	Report Count (48)
0x91, 0x02,	Output (Data,Var,Abs,No Wrap,Linear,Preferred State,No Null Position,Non-volatile)
0xC0,	End Collection

Colors

HEX codes for the colors shown in the "Controllers" menu of the Switch UI can be found in a Joy-con SPI dump starting at offset 0x6050. Body color is first followed by button color and each is 3 bytes long. These values are able to be re-written with any HEX color value to make the Joy-cons show up as different colors in the UI. The following is a list of official HEX colors recovered from SPI dumps.

Color Name	Body HEX	Button HEX
Gray / グレー	#828282	#0F0F0F
Neon Red / ネオンレッド	#FF3C28	#1E0A0A
Neon Blue / ネオンブルー	#0AB9E6	#001E1E
Neon Yellow / ネオンイエロー	#E6FF00	#142800
Neon Green / ネオングリーン	#1EDC00	#002800
Neon Pink / ネオンピンク	#FF3278	#28001E
Red / レッド	#E10F00	#280A0A
Blue / ブルー	#4655F5	#00000A
Neon Purple / ネオンパープル	#B400E6	#140014
Neon Orange / ネオンオレンジ	#FAA005	#0F0A00
Pokemon Let's Go! Pikachu / ポケットモンスター Let's Go! ピカチュウ	#FFDC00	#322800
Pokemon Let's Go! Eevee / ポケットモンスター Let's Go! イーブイ	#C88C32	#281900
Nintendo Labo Creators Contest Edition	#D7AA73	#1E1914
Animal Crossing Special Edition Left Joy-Con	#82FF96	#0A1E0A
Animal Crossing Special Edition Right Joy-Con	#96F5F5	#0A1E28
Fortnite Wildcat Yellow Left Joy-Con	#FFCC00	#1A1100
Fortnite Wildcat Blue Right Joy-Con	#0084FF	#000F1E
Mario Red & Blue Edition Joy-Con	#F04614	#1E1914

Additional Links

Reverse Engineering of the Joy-Con by Github user dekuNukem