Henry-Hiles/qmk_userspace
1
0
Fork 0
forked from mirrors/qmk_userspace
Code Pull requests Activity

Remove superfluous JTAG disable code (#6445)

Browse source 
* Remove superfluous JTAG disable code

* 32A has differently named register

* Accidentally some operators

* 32A also has different JTAG pins

* Wrap disable_jtag() in an ifndef

* Document this new define

* Rename the define, it conflicts with a LUFA thing

Also, move the ifndef wrapping to the call in keyboard_setup()
This commit is contained in:
fauxpark 2019-08-21 15:18:52 +10:00 • committed by Drashna Jaelre
parent 977c316eb1
commit f2c179de58
19 changed files with 15 additions and 94 deletions
Download patch file Download diff file Expand all files Collapse all files

17
docs/faq_debug.md
View file

@ -184,22 +184,15 @@ Pressing any key during sleep should wake host.
Arduino Leonardo and micro have **ATMega32U4** and can be used for TMK, though Arduino bootloader may be a problem.
## Enabling JTAG
## 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 ATMega*U* or AT90USB* are affected with this.
By default, the JTAG debugging interface is disabled as soon as the keyboard starts up. JTAG-capable MCUs come from the factory with the `JTAGEN` fuse set, and it takes over certain pins of the MCU that the board may be using for the switch matrix, LEDs, etc.
If you are using Teensy this isn't needed. Teensy is shipped with JTAGEN fuse bit unprogrammed to disable the function.
If you would like to keep JTAG enabled, just add the following to your `config.h`:
See this code.
```c
#define NO_JTAG_DISABLE
```
// 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.