Nosumor keyboard remake project, started on 07/Jun/2017, now finalised first prototype PCB design and started prototype production. The PCB layout was made compatible with the original Nosumor v3 front panel. (PCB manufacturer: Seeed Studio)
Features: 50x50 (mm) board area 2 mechanical keyboard switches and 3 buttons Keycap lighting (white) and 2 other independent RGB LEDs 3.5mm audio jack with TLV320AIC3110 audio codec STM32F722RE Cortex-M7 high performance MCU USB 2.0 high-speed PHY USB3370 On-board FT2232D connected to UART & JTAG Extension UART with 3.3V output
Estimated costs: Basic keyboard: £20 Complete configuration: £30 Complete with debugging: £38
Errata: No current limiting resistors with keycap LEDs (3.3V PWM direct) No pull-up resistors on data lines (internal pull-up resistors inside STM32 may or may not work) Lack of ferrite bead filter on audio AVDD
Schematic design: 
PCB top layer design: 
PCB bottom layer design: 