This is a way to take a Microsoft ergonomic bluetooth keyboard, and make it into a hard-wired keyboard running QMK. The keyboard is known under several different names: Mobile Bluetooth 5000, Mobile 6000, Sculpt mobile, and Asus rebranded I had a stack of them,since they're cheap on ebay, travel well, and are just ergo enough. The ribbon cable is 1mm pitch, which is hard to hand solder. I bought a cheap set of "pitch adapter" boards https://www.amazon.com/Double-Sided-0-4mm-1-0-Adapter-60mmx38mm/dp/B00OK42118 Cut the original ribbon cable sockets off the bluetooth board using a razor, they're hard to desolder. They're also allow the cable to be inserted on top or bottom. If I was going to do it again, I'd make the MCU connection come out the top of the keyboard and avoid the wires dangling out the bottom. As I was debugging the matrix, I started to get random failures. In desparation I tried a second MCU, but had the same problems. It turns out that the ribbon cable connections can get worn. Shave a half millimeter off the end of the ribbon cable & the errors go away. My method for discovering the matrix was to set up a KEYMAP macro that included all pins. See MATRIX_TESTING_KEYMAP if you need it. Then set up a keymap that has all printable symbols in the first 4 rows. test each key & record output. Then switch the printable symbols to the bottom 4 rows & repeat. This was enough to show the matrix. The full original keymap for the sculpt is A B C D E F G H ---> 0 b n m , . / 1 g h " 2 7 8 9 0 Del PgUp 3 p [ ] \ 4 y u i o 5 ~ - += j k l ; 5 6 a s d q w e, Up left 7 F7 F8 F9 F10 F11 F12 f -----> I J K L M N O P Q R 0 Caps FN 1 Vol+ mute Rctl vol- pgdn LCTL 2 Rshift LShift 3 Ralt LAlt 4 LGUI 5 6 bakspc 1 2 3 4 F4 F5 F6 6 Down right spc F1 F2 F3 tab 7 r t z x c v enter Esc This works with 18 cols + 8 rows on a Teensy++, or Arm based Teensy. The Astar mini has all pins exposed , so you can do 18x8 If you want a speaker, LEDs &etc, you'll need to free up a pin. I recommend joining columns R and L to the same pin. Building - edit rules.mk to set ASTAR=1 or comment it out for teensy2++