1 # Frequently Asked Build Questions
3 This page covers questions about building QMK. If you haven't yet done so, you should read the [Build Environment Setup](getting_started_build_tools.md) and [Make Instructions](getting_started_make_guide.md) guides.
5 ## Can't Program on Linux
6 You will need proper permissions to operate a device. For Linux users, see the instructions regarding `udev` rules, below. If you have issues with `udev`, a work-around is to use the `sudo` command. If you are not familiar with this command, check its manual with `man sudo` or [see this webpage](https://linux.die.net/man/8/sudo).
8 An example of using `sudo`, when your controller is ATMega32u4:
10 $ sudo dfu-programmer atmega32u4 erase --force
11 $ sudo dfu-programmer atmega32u4 flash your.hex
12 $ sudo dfu-programmer atmega32u4 reset
16 $ sudo make <keyboard>:<keymap>:dfu
18 Note that running `make` with `sudo` is generally ***not*** a good idea, and you should use one of the former methods, if possible.
20 ### Linux `udev` Rules
21 On Linux, you'll need proper privileges to access the MCU. You can either use
22 `sudo` when flashing firmware, or place these files in `/etc/udev/rules.d/`.
24 **/etc/udev/rules.d/50-atmel-dfu.rules:**
27 SUBSYSTEMS=="usb", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2ff4", MODE:="0666"
28 # Atmel USBKEY AT90USB1287
29 SUBSYSTEMS=="usb", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2ffb", MODE:="0666"
31 SUBSYSTEMS=="usb", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2ff0", MODE:="0666"
34 **/etc/udev/rules.d/52-tmk-keyboard.rules:**
36 # tmk keyboard products https://github.com/tmk/tmk_keyboard
37 SUBSYSTEMS=="usb", ATTRS{idVendor}=="feed", MODE:="0666"
39 **/etc/udev/rules.d/54-input-club-keyboard.rules:**
42 # Input Club keyboard bootloader
43 SUBSYSTEMS=="usb", ATTRS{idVendor}=="1c11", MODE:="0666"
46 ### Serial device is not detected in bootloader mode on Linux
47 Make sure your kernel has appropriate support for your device. If your device uses USB ACM, such as
48 Pro Micro (Atmega32u4), make sure to include `CONFIG_USB_ACM=y`. Other devices may require `USB_SERIAL` and any of its sub options.
50 ## Unknown Device for DFU Bootloader
52 Issues encountered when flashing keyboards on Windows are most often due to having the wrong drivers installed for the bootloader.
54 Re-running the installation script for MSYS2 may help (eg run `util/qmk_install.sh` from MSYS2/WSL) or reinstalling the QMK Toolbox may fix the issue. Alternatively, you can download and run the [`qmk_driver_installer`](https://github.com/qmk/qmk_driver_installer) package.
56 If that doesn't work, then you may need to grab the [Zadig Utility](https://zadig.akeo.ie/). Download this, and run it on the system. Then, you will need to reset your board into bootloader mode. After that, locate the device in question. If the device doesn't show up in the list (or nothing shows up in the list), you may need to enable the `List all devices` option in the `Options` menu.
58 From here, you will need to know what type of controller the board is using. You may see it listed in the Device Manager as `ATmega32U4` device (which is an AVR board), or an `STM32` device (Which is an ARM board). For AVR boards, use `libusb-win32` for the driver. For ARM boards, use the `WinUSB` driver. Once the correct driver type has been selected, click on the `Replace Driver` button, unplug your board, plug it back in, and reset it again.
62 It is no longer recommended and may cause some problem.
63 See [TMK Issue #99](https://github.com/tmk/tmk_keyboard/issues/99).
66 You can use any ID you want with editing `config.h`. Using any presumably unused ID will be no problem in fact except for very low chance of collision with other product.
68 Most boards in QMK use `0xFEED` as the vendor ID. You should look through other keyboards to make sure you pick a unique Product ID.
71 https://github.com/tmk/tmk_keyboard/issues/150
73 You can buy a really unique VID:PID here. I don't think you need this for personal use.
74 - http://www.obdev.at/products/vusb/license.html
75 - http://www.mcselec.com/index.php?page=shop.product_details&flypage=shop.flypage&product_id=92&option=com_phpshop&Itemid=1
77 ## Cortex: `cstddef: No such file or directory`
78 GCC 4.8 of Ubuntu 14.04 had this problem and had to update to 4.9 with this PPA.
79 https://launchpad.net/~terry.guo/+archive/ubuntu/gcc-arm-embedded
81 https://github.com/tmk/tmk_keyboard/issues/212
82 https://github.com/tmk/tmk_keyboard/wiki/mbed-cortex-porting#compile-error-cstddef
83 https://developer.mbed.org/forum/mbed/topic/5205/
85 ## `clock_prescale_set` and `clock_div_1` Not Available
86 Your toolchain is too old to support the MCU. For example WinAVR 20100110 doesn't support ATMega32u2.
89 Compiling C: ../../tmk_core/protocol/lufa/lufa.c
90 avr-gcc -c -mmcu=atmega32u2 -gdwarf-2 -DF_CPU=16000000UL -DINTERRUPT_CONTROL_ENDPOINT -DBOOTLOADER_SIZE=4096 -DF_USB=16000000UL -DARCH=ARCH_AVR8 -DUSB_DEVICE_ONLY -DUSE_FLASH_DESCRIPTORS -DUSE_STATIC_OPTIONS="(USB_DEVICE_OPT_FULLSPEED | USB_OPT_REG_ENABLED | USB_OPT_AUTO_PLL)" -DFIXED_CONTROL_ENDPOINT_SIZE=8 -DFIXED_NUM_CONFIGURATIONS=1 -DPROTOCOL_LUFA -DEXTRAKEY_ENABLE -DCONSOLE_ENABLE -DCOMMAND_ENABLE -DVERSION=unknown -Os -funsigned-char -funsigned-bitfields -ffunction-sections -fdata-sections -fno-inline-small-functions -fpack-struct -fshort-enums -fno-strict-aliasing -Wall -Wstrict-prototypes -Wa,-adhlns=obj_alps64/protocol/lufa/lufa.lst -I. -I../../tmk_core -I../../tmk_core/protocol/lufa -I../../tmk_core/protocol/lufa/LUFA-git -I../../tmk_core/common -std=gnu99 -include config.h -MMD -MP -MF .dep/obj_alps64_protocol_lufa_lufa.o.d ../../tmk_core/protocol/lufa/lufa.c -o obj_alps64/protocol/lufa/lufa.o
91 ../../tmk_core/protocol/lufa/lufa.c: In function 'setup_mcu':
92 ../../tmk_core/protocol/lufa/lufa.c:575: warning: implicit declaration of function 'clock_prescale_set'
93 ../../tmk_core/protocol/lufa/lufa.c:575: error: 'clock_div_1' undeclared (first use in this function)
94 ../../tmk_core/protocol/lufa/lufa.c:575: error: (Each undeclared identifier is reported only once
95 ../../tmk_core/protocol/lufa/lufa.c:575: error: for each function it appears in.)
96 make: *** [obj_alps64/protocol/lufa/lufa.o] Error 1
100 ## BOOTLOADER_SIZE for AVR
101 Note that Teensy2.0++ bootloader size is 2048byte. Some Makefiles may have wrong comment.
104 # Boot Section Size in *bytes*
106 # Teensy++ halfKay 2048
107 # Atmel DFU loader 4096 (TMK Alt Controller)
108 # LUFA bootloader 4096
110 OPT_DEFS += -DBOOTLOADER_SIZE=2048
113 ## `avr-gcc: internal compiler error: Abort trap: 6 (program cc1)` on MacOS
114 This is an issue with updating on brew, causing symlinks that avr-gcc depend on getting mangled.
116 The solution is to remove and reinstall all affected modules.
120 brew rm dfu-programmer
122 brew rm gcc-arm-none-eabi
125 brew install dfu-programmer
126 brew install dfu-util
127 brew install gcc-arm-none-eabi
131 ### avr-gcc 8.1 and LUFA
133 If you updated your avr-gcc to above 7 you may see errors involving LUFA. For example:
135 `lib/lufa/LUFA/Drivers/USB/Class/Device/AudioClassDevice.h:380:5: error: 'const' attribute on function returning 'void'`
137 For now, you need to rollback avr-gcc to 7 in brew.
140 brew uninstall --force avr-gcc
141 brew install avr-gcc@8
142 brew link --force avr-gcc@8
145 ### I just flashed my keyboard and it does nothing/keypresses don't register - it's also ARM (rev6 planck, clueboard 60, hs60v2, etc...) (Feb 2019)
146 Due to how EEPROM works on ARM based chips, saved settings may no longer be valid. This affects the default layers, and *may*, under certain circumstances we are still figuring out, make the keyboard unusable. Resetting the EEPROM will correct this.
148 [Planck rev6 reset EEPROM](https://cdn.discordapp.com/attachments/473506116718952450/539284620861243409/planck_rev6_default.bin) can be used to force an eeprom reset. After flashing this image, flash your normal firmware again which should restore your keyboard to _normal_ working order.
149 [Preonic rev3 reset EEPROM](https://cdn.discordapp.com/attachments/473506116718952450/537849497313738762/preonic_rev3_default.bin)
151 If bootmagic is enabled in any form, you should be able to do this too (see [Bootmagic docs](feature_bootmagic.md) and keyboard info for specifics on how to do this).