Install WinAVR. This is old but works well for this purpose. WinAVR is a tool set to build firmware including C compiler(gcc) and make commands. You can use CrossPack instead if you are on Mac.
Install Atmel FLIP. FLIP is a tool to program(load) firmware into AVR controller(ATMega32u4) via DFU bootloader. ATMega32u4 has DFU bootloader by factory default. You can use dfu-programmer instead if you are on Mac.
Install driver for DFU bootloader. At first time you start DFU bootloader on Chip 'Found New Hardware Wizard' will come up on Windows. If you install device driver properly you can find chip name like 'ATmega32U4' under 'LibUSB-Win32 Devices' tree on 'Device Manager'. If not you shall need to update its driver on 'Device Manager'. You will find the driver in FLIP install directory like: C:\Program Files (x86)\Atmel\Flip 3.4.5\usb. If you use dfu-programmer install its driver.

If you use PJRC Teensy you don't need step 2 and 3, just get Teensy loader.

Download source

You can find firmware source at github: https://github.com/tmk/tmk_keyboard

If you are familiar with Git tools you are recommended to use it.
If not you can download zip archive from: https://github.com/tmk/tmk_keyboard/archive/master.zip

Build firmware

Open terminal window to get access to commands. You can use cmd in Windows or Terminal.app on Mac OSX. In Windows press Windows key and R then enter cmd in Run command dialog showing up.
Move to project directory in the firmware source.

cd tmk_keyboard/{keyboard or converter}/
Build firmware using GNU make command. You'll see _.hex file in that directory unless something unexpected occurs in build process.

mkae -f Makefile. clean make -f Makefile.

Program Controller

Sock AVR USB chip including ATmega32U4 has DFU bootloader by factory default, you can use DFU tools for this purpose. FLIP is a DFU tool on Windows offered by Atmel. Open source command line DFU tool dfu-programmer also supports AVR chips, which run on Linux, Mac OSX and even Windows. If you have a PJRC Teensy you should use Teensy Loader.

DFU bootloader

To program AVR chip with DFU bootloader use FLIP or dfu-programmer. If you have a proper program command in Makefile just type this.

FLIP has two version of tool, GUI app and command line program. If you want GUI see tutorial section below. To use command line tool run this command. Note that you need to set PATH variable properly.

$ make -f Makefile.<variant> flip

To program with dfu-programmer run:

$ make -f Makefile.<variant> dfu

Teensy

If you have PJRC Teensy see instruction of Teensy Loader at: http://www.pjrc.com/teensy/loader.html Or use this command if you have command line version of Teensy Loader installed.

$ make -f Makefile.<variant> teensy

Other programmer

You may want to use other you favorite programmer like avrdude with AVRISPmkII, Aruduino or USBasp. In that case you can still use make target program for build with configuring PROGRAM_CMD in Makefile.

$ make -f Makefile.<variant> program

FLIP GUI tutorial

On menu bar click Device -> Select, then. ATmega32u4.
On menu bar click Settings -> Communication -> USB, then click 'Open' button on 'USB Port Connection' dialog. At this point you'll see greyouted widgets on the app get colored and ready.
On menu bar click File -> Load HEX File, then select your firmware hex file on File Selector dialog.
On 'Operations Flow' panel click 'Run' button to load the firmware binary to the chip. Note that you should keep 'Erase', 'Blank Check', 'Program' and 'Verify' check boxes selected.
Re-plug USB cord or click 'Start Application' button to restart your controller. Done.

See also these instaructions if you need.

Makefile Options

1. MCU and Frequency.

MCU = atmega32u4       # Teensy 2.0
#MCU = at90usb1286      # Teensy++ 2.0
F_CPU = 16000000

2. Features

Note that comment out to disable them.

MOUSEKEY_ENABLE = yes	# Mouse keys
PS2_MOUSE_ENABLE = yes	# PS/2 mouse(TrackPoint) support
EXTRAKEY_ENABLE = yes	# Enhanced feature for Windows(Audio control and System control)
NKRO_ENABLE = yes		# USB Nkey Rollover

3. Programmer

Optional. Set proper command for your controller, bootloader and programmer.

# for PJRC Teensy
PROGRAM_CMD = teensy_loader_cli -mmcu=$(MCU) -w -v $(TARGET).hex

# for Atmel chip with DFU bootloader
PROGRAM_CMD = dfu-programmer $(MCU) flash $(TARGET).hex

# avrdude with other methods
PROGRAM_CMD = avrdude -p $(MCU) -c avrispmkII -P USB -U flash:w:$(TARGET).hex
PROGRAM_CMD = avrdude -p $(MCU) -c usbasp -U flash:w:$(TARGET).hex
PROGRAM_CMD = avrdude -p $(MCU) -c arduino -P COM1 -b 57600 -U flash:w:$(TARGET).hex

Config.h Options

1. USB vendor/product ID and device description

#define VENDOR_ID       0xFEED
#define PRODUCT_ID      0xBEEF
/* device description */
#define MANUFACTURER    t.m.k.
#define PRODUCT         Macway mod
#define DESCRIPTION     t.m.k. keyboard firmware for Macway mod

2. Keyboard matrix configuration

#define MATRIX_ROWS 8
#define MATRIX_COLS 8
#define MATRIX_HAS_GHOST

3. Mouse keys

4. PS/2 mouse

5. COMMAND key combination

#define IS_COMMAND() (keyboard_report->mods == (MOD_BIT(KB_LSHIFT) | MOD_BIT(KB_RSHIFT)))

Keymap

Many of existent projects offer keymap framework to define your own keymap easily. The following will explain how you can define keymap using this framework. Instead, you can also implement your own keymap_get_action() to return action code for each key if you want.

This is keymap example for HHKB keyboard. Keymap is defined in keymaps[] array.

static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
    /* Keymap 0: Default Layer
     * ,-----------------------------------------------------------.
     * |Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `|
     * |-----------------------------------------------------------|
     * |Tab  |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]|Backs|
     * |-----------------------------------------------------------|
     * |Contro|  A|  S|  D|  F|  G|  H|  J|  K|  L|Fn1|  '|Enter   |
     * |-----------------------------------------------------------|
     * |Shift   |  Z|  X|  C|  V|  B|  N|  M|  ,|  .|  /|Shift |Fn0|
     * `-----------------------------------------------------------'
     *       |Gui|Alt  |Space                  |Alt  |Fn2|
     *       `-------------------------------------------'
     */
    KEYMAP(ESC, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSLS,GRV, \
           TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSPC, \
           LCTL,A,   S,   D,   F,   G,   H,   J,   K,   L,   FN1, QUOT,ENT, \
           LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, SLSH,RSFT,FN0, \
                LGUI,LALT,          SPC,                RALT,FN3),
    /* Keymap 1: colemak */
    KEYMAP(ESC, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSLS,GRV, \
           TAB, Q,   W,   F,   P,   G,   J,   L,   U,   Y,   SCLN,LBRC,RBRC,BSPC, \
           BSPC,A,   R,   S,   T,   D,   H,   N,   E,   I,   O,   QUOT,ENT, \
           LSFT,Z,   X,   C,   V,   B,   K,   M,   COMM,DOT, SLSH,RSFT,FN0, \
                LGUI,LALT,          SPC,                RALT,FN2),
};

static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
    /* Overlay 0: HHKB mode (HHKB Fn)
     * ,-----------------------------------------------------------.
     * |Pwr| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|Ins|Del|
     * |-----------------------------------------------------------|
     * |Caps |   |   |   |   |   |   |   |Psc|Slk|Pus|Up |   |Backs|
     * |-----------------------------------------------------------|
     * |Contro|VoD|VoU|Mut|   |   |  *|  /|Hom|PgU|Lef|Rig|Enter   |
     * |-----------------------------------------------------------|
     * |Shift   |   |   |   |   |   |  +|  -|End|PgD|Dow|Shift |   |
     * `-----------------------------------------------------------'
     *      |Gui |Alt  |Space                  |Alt  |Gui|
     *      `--------------------------------------------'
     */ 
    KEYMAP(PWR, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, INS, DEL, \
           CAPS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,PSCR,SLCK,PAUS,UP,  TRNS,BSPC, \
           LCTL,VOLD,VOLU,MUTE,TRNS,TRNS,PAST,PSLS,HOME,PGUP,LEFT,RGHT,ENT, \
           LSFT,TRNS,TRNS,TRNS,TRNS,TRNS,PPLS,PMNS,END, PGDN,DOWN,RSFT,TRNS, \
                LGUI,LALT,          SPC,                RALT,RGUI),
    /* Overlay 1: Mouse mode (Semicolon)
     * ,-----------------------------------------------------------.
     * |Esc| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|Ins|Del|
     * |-----------------------------------------------------------|
     * |Tab  |   |   |   |   |   |MwL|MwD|MwU|MwR|   |   |   |Backs|
     * |-----------------------------------------------------------|
     * |Contro|   |   |   |   |   |McL|McD|McU|McR|   |   |Return  |
     * |-----------------------------------------------------------|
     * |Shift   |   |   |   |   |Mb3|Mb2|Mb1|Mb4|Mb5|   |Shift |   |
     * `-----------------------------------------------------------'
     *      |Gui |Alt  |Mb1                    |Alt  |   |
     *      `--------------------------------------------'
     * Mc: Mouse Cursor / Mb: Mouse Button / Mw: Mouse Wheel 
     */
    KEYMAP(ESC, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, INS, DEL, \
           TAB, TRNS,TRNS,TRNS,TRNS,TRNS,WH_L,WH_D,WH_U,WH_R,TRNS,TRNS,TRNS,BSPC, \
           LCTL,TRNS,ACL0,ACL1,ACL2,TRNS,MS_L,MS_D,MS_U,MS_R,TRNS,QUOT,ENT, \
           LSFT,TRNS,TRNS,TRNS,TRNS,BTN3,BTN2,BTN1,BTN4,BTN5,SLSH,RSFT,TRNS, \
                LGUI,LALT,          BTN1,               RALT,TRNS),
};

static const uint16_t PROGMEM fn_actions[] = {
    ACTION_OVERLAY(0),                            // FN0
    ACTION_OVERLAY_TAP_KEY(1, KC_SCLN),           // FN1
    ACTION_OVERLAY_TOGGLE(1),                     // FN2
};

1. Keycode

See common/keycode.h. Keycode is 8bit internal code to inidicate action performed on key in keymap. Keycode has KC_ prefixed symbol respectively. Most of keycodes like KC_A have simple action register key on press and unregister on release, on the other some of keycodes has some special actions like Fn keys, Media contorl keys, System control keys and Mouse keys.

In KEYMAP definition you need to omit prefix part KC_ of keycode to keep keymap compact. For example, just use A instead you place KC_A in KEYMAP. Some keycodes has 4-letter short name in addition to descriptive name, you'll prefer short one in KEYMAP.

1.0 Other key

KC_NO for no aciton
KC_TRNS for transparent layer

1.1 Normal key

KC_A to KC_Z, KC_1 to KC_0 for alpha numeric key
KC_MINS, KC_EQL, KC_GRV, KC_RBRC, KC_LBRC, KC_COMM, KC_DOT, KC_BSLS, KC_SLSH, KC_SCLN, KC_QUOT
KC_ESC, KC_TAB, KC_SPC, KC_BSPC, KC_ENT, KC_DEL, KC_INS
KC_UP, KC_DOWN, KC_RGHT, KC_LEFT, KC_PGUP, KC_PGDN, KC_HOME, KC_END
KC_CAPS, KC_NLCK, KC_SLCK, KC_PSCR, KC_PAUS, KC_APP, KC_F1 to KC_F24
KC_P1 to KC_P0, KC_PDOT, KC_PCMM, KC_PSLS, KC_PAST, KC_PMNS, KC_PPLS, KC_PEQL, KC_PENT for keypad.

1.2 Modifier

There are 8 modifiers which has discrimination between left and right.

KC_LCTL and KC_RCTL for Control
KC_LSFT and KC_RSFT for Shift
KC_LALT and KC_RALT for Alt
KC_LGUI and KC_RGUI for Windows key or Command key in Mac

1.3 Mousekey

KC_MS_U, KC_MS_D, KC_MS_L, KC_MS_R for mouse cursor
KC_WH_U, KC_WH_D, KC_WH_L, KC_WH_R for mouse wheel
KC_BTN1, KC_BTN2, KC_BTN3, KC_BTN4, KC_BTN5 for mouse buttons

1.4 System & Media key

KC_PWR, KC_SLEP, KC_WAKE for Power, Sleep, Wake
KC_MUTE, KC_VOLU, KC_VOLD for audio volume control
KC_MNXT, KC_MPRV, KC_MSTP, KC_MPLY, KC_MSEL for media control
KC_MAIL, KC_CALC, KC_MYCM for application launch
KC_WSCH, KC_WHOM, KC_WBAK, KC_WFWD, KC_WSTP, KC_WREF, KC_WFAV for web browser operation

1.5 Fn key

KC_FNnn are Fn keys which not given any action at the beginning unlike most of keycodes has its own action. To use these keys in KEYMAP you need to assign action you want at first. Action of Fn is defined in fn_actions[] and index of the array is identical with number part of KC_FNnn. Thus KC_FN0 designates action defined in first element of the array. 32 Fn keys can be defined at most.

Keycode Table

See keycode table in doc/keycode.txt or common/keycode.h for the detail or other keycodes.

In regard to implementation side most of keycodes are identical with [HID usage] sent to host for real and some virtual keycodes are defined to support special actions. [HID usage]: http://www.usb.org/developers/devclass_docs/Hut1_11.pdf

2. Action

See common/action.h. Action is a 16bit code and defines function to perform on events of a key like press, release, hold and tap. You can define various actions to use various action codes.

Most of keys just register 8bit keycodes(HID usage) to host, while to support other complex features needs 16bit extended action codes internally. But using 16bit action codes in keymap results in double size in memory against keycodes. To avoid this waste 8bit keycodes are used in KEYMAP to define instead of action codes.

You can just use keycodes of Normal key, Modifier, Mousekey and System & Media key in keymap to indicate corresponding actions, instead of action code itself. In the end you can map most of keys just with 8bit keycodes.

To use other special actions you should use Fn key keycode defined with such action yourself.

2.1 Key action

Key is simple action that registers keycode on press event of key and unregister on release.

2.1.1 Normal key and Modifier

You can define Key action on 'A' key with:

ACTION_KEY(KC_A)
ACTION_KEY(KC_LSHIFT)

***** 2.1.2 Key with modifiers Say you want to assign a key to Shift + 1 to get charactor '!' or Alt + Tab to switch windows.

ACTION_MOD_KEY(KC_LSHIFT, KC_1)
ACTION_MOD_KEY(KC_LALT, KC_TAB)

Or Alt,Shift + Tab can be defined.

ACTION_MODS_KEY((MOD_BIT(KC_LALT) | MOD_BIT(KC_LSHIFT)), KC_TAB)

These actions are comprised of strokes of modifiers and a key. Macro action is needed if you want more complex key strokes.

2.2 Layer Actions

2.2.0 Return to Default Layer

This sets default layer into current layer. With this action you can return to default layer. with clear other layers.

ACTION_DEFAULT_LAYER

2.2.1 Keymap

Keymap action validate given layer which ranges from 0 to 15.

ACTION_KEYMAP_MOMENTARY(layer)
ACTION_KEYMAP_TOGGLE(layer)
ACTION_KEYMAP_TAP_KEY(layer, key)
ACTION_KEYMAP_TAP_TOGGLE(layer)

2.2.2 Overlay

Overlay action validate

ACTION_KEYMAP_MOMENTARY(layer)
ACTION_KEYMAP_TOGGLE(layer)
ACTION_KEYMAP_TAP_KEY(layer, key)
ACTION_KEYMAP_TAP_TOGGLE(layer)

2.2.3 Set Default layer

These acitons change default layer to given layer.

ACTION_SET_DEFAULT_LAYER(layer)

2.3 Macro action

TBD

Macro action indicates complex key strokes.

MACRO( MD(LSHIFT), D(D), END )
MACRO( U(D), MU(LSHIFT), END )
MACRO( I(255), T(H), T(E), T(L), T(L), W(255), T(O), END )

2.3.1 Normal mode

I() change interavl of stroke.
D() press key
U() release key
T() type key(press and release)
W() wait
MD() modifier down
MU() modifier up
END end mark

2.3.2 Extended mode

TODO: sample impl See keyboard/hhkb/keymap.c for sample.

2.4 Function action

TBD

There are two type of action, normal Function and tappable Function. These actions call user defined function with id, opt, and key event information as arguments.

2.4.1 Function

To define normal Function action in keymap use this.

ACTION_FUNCTION(id, opt)

2.4.2 Function with tap

To define tappable Function action in keymap use this.

ACTION_FUNCTION_TAP(id, opt)

2.4.3 Implement user function

Function actions can be defined freely with C by user in callback function:

void keymap_call_function(keyrecord_t *event, uint8_t id, uint8_t opt)

This C function is called every time key is operated, argument id selects action to be performed and opt can be used for option. Functon id can be 0-255 and opt can be 0-15.

keyrecord_t is comprised of key event and tap count. keyevent_t indicates which and when key is pressed or released. From tap_count you can know tap state, 0 means no tap. These information will be used in user function to decide how action of key is performed.

typedef struct {
    keyevent_t  event;
    uint8_t     tap_count;
} keyrecord_t;

typedef struct {
    key_t    key;
    bool     pressed;
    uint16_t time;
} keyevent_t;

typedef struct {
    uint8_t col;
    uint8_t row;
} key_t;

TODO: sample impl See keyboard/hhkb/keymap.c for sample.

3. Layer

Layer is key-action map to assign action to every physical key. You can define multiple layers in keymap and make layers active out of keymap during operation at will.

First layer is indexed by 0 which usually become default layer and active in initial state.

You can define 16 layers at most in each keymaps[] and overlays[].

you can define a layer with placing keycode symbols separated with comma in KEYMAP, which is formed with resemblance to physical keyboard layout so as you can easily put keycode on place you want to map. You can define most of keys with just using keycodes except for Fn key serving special actions.

4. Layer switching

You can have some ways to switch layer with these actions. There are two kind of layer switch action Layer Set and Layer Bit and two type of switching behaviour Momentary and Toggle.

4.1 Momentary switching

Momentary switching changes layer only while holding Fn key.

4.1.1 Momentary Set

This action makes Layer 1 active on key press event and inactive on release event..

ACTION_KEYMAP_MOMENTARY(1)

It switches to destination layer immediately when key is pressed, after that actions on keymap of destination layer is perfomed. Thus you shall need to place action to come back on destination layer, or you will be stuck in destination layer without way to get back. To get back to default layer you can use this action.

ACTION_LAYER_DEFAULT

4.1.2 Momentary Bit

This Layer Bit action performs XOR 1 with current layer on both press and release event. If you are on Layer 0 now next layer to switch will be Layer 1. To come back to previous layer you need to place same action on destination layer.

ACTION_LAYER_BIT(1)

4.2 Toggle switching

Toggle switching changes layer after press then release. You keep being on the layer until you press key to return.

4.2.1 Toggle Set

This Layer Set Toggle action is to set Layer 1 to current layer on release and do none on press.

ACTION_LAYER_SET_TOGGLE(1)

To get back to default layer you can use this action.

ACTION_LAYER_DEFAULT

4.2.2 Toggle Bit

This Layer Bit Toggle action is to XOR 1 with current layer on release and do none on press. If you are on Layer 2 you'll switch to Layer 3 on press. To come back to previous layer you need to place same action on destination layer.

ACTION_LAYER_BIT_TOGGLE(1)

4.3 Momentary switching with Tap key

These actions switch to layer only while holding Fn key and register key on tap. Tap means to press and release key quickly.

ACTION_LAYER_SET_TAP_KEY(2, KC_SCLN)
ACTION_LAYER_SET_BIT_KEY(2, KC_SCLN)

With these you can place layer switching function on normal alphabet key like ; without losing its original register function.

4.4 Momentary switching with Tap Toggle

This changes layer only while holding Fn key and toggle layer after several taps. Tap means to press and release key quickly.

ACTION_LAYER_SET_TAP_TOGGLE(layer)
ACTION_LAYER_BIT_TAP_TOGGLE(layer)

Number of taps can be defined with TAPPING_TOGGLE in config.h, 5 by default.

Legacy Keymap

This was used in prior version and still works due to legacy support code in common/keymap.c. Legacy keymap doesn't support many of features that new keymap offers.

In comparison with new keymap how to define Fn key is different. It uses two arrays fn_layer[] and fn_keycode[]. The index of arrays corresponds with postfix number of Fn key. Array fn_layer[] indicates destination layer to switch and fn_keycode[] has keycodes to send when tapping Fn key.

In following setting example, Fn0, Fn1 and Fn2 switch layer to 1, 2 and 2 respectively. Fn2 registers Space key when tap while Fn0 and Fn1 doesn't send any key.

static const uint8_t PROGMEM fn_layer[] = {
    1,              // Fn0
    2,              // Fn1
    2,              // Fn2
};

static const uint8_t PROGMEM fn_keycode[] = {
    KC_NO,          // Fn0
    KC_NO,          // Fn1
    KC_SPC,         // Fn2
};

Debuging

Use PJRC's hid_listen to see debug messages. You can use the tool for debug even if firmware use LUFA stack.

You will see output from firmware like this.

r/c 01234567
00: 00000000
01: 00000000
02: 00000000
03: 00000000
04: 00000000
05: 00000000
06: 00000000
07: 00000000

---- action_exec: start -----
EVENT: 0307u(22511)
Tapping: Tap release(2)
ACTION: ACT_LAYER[5:2C]
LAYER_PRESSED: Tap: unregister_code
TAPPING_KEY=0307u(22511):2
processed: 0307u(22511):2

Tapping: End(Timeout after releasing last tap): FFFFu(22715)
TAPPING_KEY=0000u(0):0

Magic Comannds

To see help press Magic + H.

Magic key bind may be LShift + RShift in many project, but Power key on ADB converter. Magic keybind can be vary on each project, check config.h in project directory.

Following commands can be also executed with Magic + key. In console mode Magic keybind is not needed.

----- Command Help -----
c:      enter console mode
d:      toggle debug enable
x:      toggle matrix debug
k:      toggle keyboard debug
m:      toggle mouse debug
p:      toggle print enable
v:      print device version & info
t:      print timer count
s:      print status
0/F10:  switch to Layer0
1/F1:   switch to Layer1
2/F2:   switch to Layer2
3/F3:   switch to Layer3
4/F4:   switch to Layer4
PScr:   power down/remote wake-up
Caps:   Lock Keyboard(Child Proof)
Paus:   jump to bootloader

Boot Magic

Magic commands are executed when boot time. Press Magic command key then pulgin.

Define these macros in config.h.

IS_BOOTMAGIC_DEBUG
IS_BOOTMAGIC_BOOTLOADER

TODO: sample impl See keyboard/hhkb/config.h for sample.

Start Your Own Project

Files & Directories

Top

common/ - common codes
protocol/ - keyboard protocol support
keyboard/ - keyboard projects
converter/ - protocol converter projects
doc/ - documents
common.mk - Makefile for common
protoco.mk - Makefile for protocol
rules.mk - Makefile for build rules

Common

action.[ch]
action_macro.[ch]
bootloader.[ch]
command.[ch]
controller_teensy.h
debug.[ch]
host.[ch]
host_driver.h
keyboard.[ch]
keycode.h
keymap.[ch]
led.h
matrix.h
mousekey.[ch]
print.[ch]
report.h
sendchar.h
sendchar_null.c
sendchar_uart.c
timer.[ch]
uart.[ch]
util.[ch]

Keyboard Protocols

lufa/ - LUFA USB stack
pjrc/ - PJRC USB stack
vusb/ - Objective Development V-USB
iwrap/ - Bluetooth HID for Bluegiga iWRAP
ps2.c - PS/2 protocol
adb.c - Apple Desktop Bus protocol
m0110.c - Macintosh 128K/512K/Plus keyboard protocol
news.c - Sony NEWS keyboard protocol
x68k.c - Sharp X68000 keyboard protocol
serial_soft.c - Asynchronous Serial protocol implemented by software

License

Under GPL 2 or later. Some protocol files are under Modified BSD License. LUFA, PJRC and V-USB stack have their own license respectively.