Perplexity is a 34-36 key split keyboard with a lot of features:
The Perplexity Viewer allows you to show and hide the different sets of thumb cluster positions to assist in choosing which layout you will use.Go to viewer
Download the gerber files and KiCad project, licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.Download zip archive
Other than the keyboard layouts, here are all of the options and how to use them:
On the secondary half, you can solder an MCP23017 IO expander chip instead of a Pro Micro. You will need to use I2C instead of a serial connection between the two halves.
By default, the PCB uses a serial connection between the two halves. If you need to change it to I2C, you can solder the jumper next to the footprint for the TRRS connector and solder two 2.2k resistors in the resistor footprints.
You can use either a PJ-320A TRRS connector or a TYPE-C-31-M-12 connector. However, you cannot use the Type-C connector if you want to use the DIP switch.
Underneath the third column, there are footprints for two SMD tact switches or two SMD LEDs (0805 package). To use the tact switches, you will need to solder diodes to the two rotated footprints nearest to the tact switches. To use the LEDs, you will need to solder 220 ohm resistors (also 0805 package) to the resistor footprints located near the bottom switch in the fourth column.
Next to the USB Type-C connector footprint, there is a footprint for a single SMD DIP switch (part number DSIC01LSGET on LCSC). This can be used in QMK, it does not function as a power switch.
An SSD1306 OLED display can be placed over the controller. To connect it, solder the jumpers on the opposite side of the PCB as you are soldering the OLED.
There are two options for positioning a reset switch; the first is on the bottom side of the board under the controller, and the second is below the USB-C footprint. The two positions use different footprints. If you use the footprint below the USB-C footprint, you need to cut off one of the mounting pins on the switch, and you cannot use some thumb key positions. The switch is not necessary on a half that uses an MCP23017.