You've finished assembling one or both halves of your split keyboard, but your OLED display doesn't work. In this article you'll find what you can do to fix it.
Sleep mode
By default, the display will turn off after around ten seconds, after the last keypress. Hit a key and the display should become active again.
The display should turn on when you just plug the keyboard in, however, so if the display won't work, follow the next steps.
Flash both halves
You should flash both halves of the keyboard at least once. If you don't, then the microcontroller won't know how to drive the display. Also see When do I need to flash my microcontroller?
Verify if the OLED is enabled
The default firmware will have the OLED enabled, but if you made custom firmware or have altered your keymap, you may have inadvertedly disabled the OLED. If you build your own firmware from the source code, check whether the following line exists in your rules.mk file:
OLED_ENABLE = yes # Enables the use of OLED displays
OLED_DRIVER = SSD1306 # Selects the right driver
Verify if anything is being written to the display
The default firmware will be writing a logo and/or layer state to the display. If you're compiling your own firmware from source, you may have deleted the statements in the code that write to the displays. If you're not writing data to the display, it will appear like it won't work. Try flashing the default firmware to see if that makes the displays show something. Also see the Firmware step of your build guide, like Kyria Build Guide: Kyria Firmware.
Check the resistors
Depending on where you sourced your OLED display, you may or may not need a resistor. Generally, for displays sold through splitkb.com, you will need resistors installed. You should check the Resistor build step in your build guide, such as Kyria Build Guide: Resistors.
Verify whether you have the solder joints formed correctly. You may apply some heat to reflow the solder, and might want to apply some more solder.
Check whether the OLED display jumpers are jumped correctly
On some boards like the Kyria and the Corne, one of the steps in the build guide is to solder four sets of jumpers underneath the microcontroller, which you need to connect to one another in order for the OLED display to work correctly. Make sure enough solder was added to the pads. Each set should connect to itself, but not to another set, so make sure there's only a bridge between each individual set as shown in the image below.
Check the display for damage
The display should not have cracks or otherwise have visible damage. If this was a result of shipping, please send a photo of the display and a photo of the packaging to support@splitkb.com and we will help you get a new display.
Final steps
If all these steps do not work, you might have a defective display. If you purchased a custom built keyboard through splitkb.com, the display will have been tested before it was shipped, and it might have broken during transit. Please get in touch with support@splitkb.com and we will make sure to have the situation resolved.
If you've purchased a kit including the display, please get in touch with support@splitkb.com and we will help you troubleshoot your display. You can also choose to purchase a new display here.