qmk_firmware/FAQ.md

Documents You Need To Read

Read these yet?

1. First README under top directory : https://github.com/tmk/tmk_keyboard/blob/master/README.md
2. For Build: https://github.com/tmk/tmk_keyboard/blob/master/doc/build.md
3. And README under each project(keyboard/converter) directory

Note that you should read two README.

Build

How to Build

See this first! https://github.com/tmk/tmk_keyboard/blob/master/doc/build.md

In short,

$ make clean
$ make [KEYMAP=...]

Do 'make clean' before 'make'

You'll need make clean after you edit config.h or change options like KEYMAP.

Frist remove all files made in previous build,

$ make clean

then build new frimware.

$ make [KEYMAP=...]

Also you can always try make clean when you get other strange result during build.

WINAVR is obsolete

It is no longer recommended and may cause some problem. See Issue #99.

USB stack: LUFA or PJRC?

Use LUFA.

PJRC stack won't be supported actively anymore. There is no reason to hesitate to use LUFA except for binary size(about 1KB lager?). But PJRC is still very useful for debug and development purpose. See also Issue #50 and Issue #58.

Edit configuration but not change

Try these.

1. make clean

This will be needed when you edit config.h.

2. Remove Drivers from Device Manager(Windows)

Windows only. Linux, OSX and other OS's doesn't require this. It looks like Windows keeps using driver installed when device was connected first time even after the device changes its configuration. To load proper drivers for new configuration you need to remove existent drivers from Drvice Manager.

You will need this after editing CONSOLE_ENABLE, NKRO_ENABLE, EXTRAKEY_ENABLE or MOUSEKEY_ENABLE option in Makefile.

Keymap

Power key doesn't work

Use KC_PWR instead of KC_POWER or vice versa.

• KC_PWR works with Windows and Linux, not with OSX.
• KC_POWER works with OSX and Linux, not with Windows.

http://geekhack.org/index.php?topic=14290.msg1327264#msg1327264

Oneshot modifier

Solves my personal 'the' problem. I often got 'the' or 'THe' wrongly instead of 'The'. Oneshot Shift mitgates this for me. https://github.com/tmk/tmk_keyboard/issues/67

Modifier/Layer stuck

Modifier keys or layers can be stuck unless layer switching is configured properly. For Modifier keys and layer actions you have to place KC_TRANS on same position of destination layer to unregister the modifier key or return to previous layer on release event.

https://github.com/tmk/tmk_keyboard/blob/master/doc/keymap.md#31-momentary-switching http://geekhack.org/index.php?topic=57008.msg1492604#msg1492604

Mechanical Lock Switch Support

https://github.com/tmk/tmk_keyboard#mechanical-locking-support

This feature is for mechanical lock switch like this Alps one. http://deskthority.net/wiki/Alps_SKCL_Lock

Using enabling this feature and using keycodes LCAP, LNUM or LSCR in keymap you can use physical locking CapsLock, NumLock or ScrollLock keys as you expected.

Old vintage mechanical keyboards occasionally have lock switches but modern ones don't have. You don't need this feature in most case and just use CAPS for Capslock.

Degug Console

hid_listen can't recognize device

When debug console of your device is not ready you will see like this:

Waiting for device:.........

once the device is pluged in then hid_listen finds it you will get this message:

Waiting for new device:.........................
Listening:

Check if you can't get this 'Listening:' message:

• build with CONSOLE_ENABLE=yes in Makefile.

Can't get message on console

Check:

• hid_listen finds your device. See above.
• Enable debug with pressing Magic+d. See Magic Commands.
• set debug_enable=yes usually in matrix_init() in matrix.c.
• try using 'print' function instead of debug print. See common/print.h.
• disconnect other devices with console function. See Issue #97.

Linux or UNIX like system requires Super User privilege

Just use 'sudo' to execute hid_listen with privilege.

$ sudo hid_listen

Or add an udev rule for TMK devices with placing a file in rules directory. The directory may vary on each system.

File: /etc/udev/rules.d/52-tmk-keyboard.rules(in case of Ubuntu)

# tmk keyboard products     https://github.com/tmk/tmk_keyboard
SUBSYSTEMS=="usb", ATTRS{idVendor}=="feed", MODE:="0666"

---

Miscellaneous

NKRO Doesn't work

1. Build with this option of Makefile

   NKRO_ENABLE = yes

2. After boot keyboard may be in boot mode(6KRO), you will need to replug keyboard to enable NKRO.

3. Or use Magic N command to toggle NKRO function.(LShift+RShift+N by default)

TrackPoint needs reset circuit(PS/2 mouse support)

Without reset circuit you will have inconsistent reuslt due to improper initialize of the hardware. See circuit schematic of TPM754.

• http://geekhack.org/index.php?topic=50176.msg1127447#msg1127447
• http://www.mikrocontroller.net/attachment/52583/tpm754.pdf

Can't read comlumn of matrix beyond 16

Use 1UL<<16 intead of 1<<16 in read_cols() in matrix.h when your columns goes beyond 16.

In C 1 means one of int type which is 16bit in case of AVR so you can't shift left more than 15. You will get unexpected zero when you say 1<<16. You have to use unsigned long type with 1UL.

http://deskthority.net/workshop-f7/rebuilding-and-redesigning-a-classic-thinkpad-keyboard-t6181-60.html#p146279

Pull-up Resistor

In some case converters needed to have pull-up resistors to work correctly. Place the resistor between VCC and signal line in parallel.

For example:

Keyboard       Conveter
               ,------.
5V------+------|VCC   |
        |      |      |
        R      |      |
        |      |      |
Signal--+------|PD0   |
               |      |
GND------------|GND   |
               `------'
R: 1K Ohm resistor

https://github.com/tmk/tmk_keyboard/issues/71

Arduino Micro's pin naming is confusing

Note that Arduino Micro PCB marking is different from real AVR port name. D0 of Arduino Micro is not PD0, PD0 is D3. Check schematic yourself. http://arduino.cc/en/uploads/Main/arduino-micro-schematic.pdf

Bootloader jump doesn't work

Properly configure boot section size in Makefile. With wrong section size bootloader won't probably start with Magic command and Boot Magic.

• https://github.com/tmk/tmk_keyboard#magic-commands
• https://github.com/tmk/tmk_keyboard#bootloader

# Boot Section Size in *bytes*
#   Teensy halfKay   512
#   Teensy++ halfKay 1024
#   Atmel DFU loader 4096       (TMK Alt Controller)
#   LUFA bootloader  4096
#   USBaspLoader     2048
OPT_DEFS += -DBOOTLOADER_SIZE=4096

http://geekhack.org/index.php?topic=12047.msg1292018#msg1292018

Special Extra key doesn't work(System, Audio control keys)

You need to define EXTRAKEY_ENABLE in makefile to use them in TMK.

EXTRAKEY_ENABLE = yes          # Audio control and System control

http://deskthority.net/workshop-f7/tmk-keyboard-firmware-collection-t4478-60.html#p157919

Wakeup from sleep doesn't work

In Windows check Allow this device to wake the computer setting in Power Management property tab of Device Manager. Also check BIOS setting.

Pressing any key during sleep should wake host.

Using Arduino?

Note that Arduino pin naming is different from actual chip. For example, Arduino pin D0 is not PD0. Check circuit with its schematics yourself.

• http://arduino.cc/en/uploads/Main/arduino-leonardo-schematic_3b.pdf
• http://arduino.cc/en/uploads/Main/arduino-micro-schematic.pdf

Arduino leonardo and micro have ATMega32U4 and can be used for TMK, though Arduino bootloader may be a problem.

Using PF4-7 pins of USB AVR?

You need to set JTD bit of MCUCR yourself to use PF4-7 as GPIO. Those pins are configured to serve JTAG function by default. MCUs like ATMegaU or AT90USB* are affeteced with this.

If you are using Teensy this isn't needed. Teensy is shipped with JTAGEN fuse bit unprogrammed to disable the function.

See this code.

    // JTAG disable for PORT F. write JTD bit twice within four cycles.
    MCUCR |= (1<<JTD);
    MCUCR |= (1<<JTD);

https://github.com/tmk/tmk_keyboard/blob/master/keyboard/hbkb/matrix.c#L67

And read 26.5.1 MCU Control Register – MCUCR of ATMega32U4 datasheet.

Adding LED indicators of Lock keys

You need your own LED indicators for CapsLock, ScrollLock and NumLock? See this post.

http://deskthority.net/workshop-f7/tmk-keyboard-firmware-collection-t4478-120.html#p191560