project webpage: https://frank-buss.de/kerberos/

New Kerberos 2 design

See the kicad directory for the current schematic and board. Here is a PDF export of the current schematic.

planned new features

• Mirror MIDI-in to thru and out

• USB MIDI device implementation

• USB host implementation for connecting USB keyboards, if possible

• SD-card for storing more programs and data

Kerberos 2 parts

FPGA with 8 MB integrated RAM: https://eu.mouser.com/ProductDetail/GOWIN-Semiconductor/GW1NR-LV4QN88C6-I5?qs=wnTfsH77Xs4Nd00MqWDpJw%3D%3D

16 MB flash: https://lcsc.com/product-detail/NOR-FLASH_Winbond-Elec-W25Q128JVSIQ_C113767.html

Microcontroller for FPGA powerup sequencing, updating the flash, and booting the FPGA: RP2040

USB-C connector: https://lcsc.com/product-detail/USB-Connectors_XUNPU-TYPEC-304J-BCP16_C2835315.html

12 MHz oscillator: https://lcsc.com/product-detail/Oscillators_Shenzhen-SCTF-Elec-SX3M12-000M20F30TNN_C2901561.html

Schottky Diode: https://lcsc.com/product-detail/span-style-background-color-ff0-Schottky-span-Barrier-Diodes-SBD_MDD-Microdiode-Electronics-SS34_C8678.html

16 Bit Level Shifter: https://lcsc.com/product-detail/Translators-Level-Shifters_Nexperia-74ALVC164245DGG-11_C5531.html

8 x 33 ohm resistor network: https://lcsc.com/product-detail/Resistor-Networks-Arrays_UNI-ROYAL-Uniroyal-Elec-16P8WGF330JT4E_C422182.html

SD-card: https://lcsc.com/product-detail/span-style-background-color-ff0-SD-span-span-style-background-color-ff0-Card-span-Connectors_MOLEX-5033981892_C428492.html

internal reset button: https://lcsc.com/product-detail/Tactile-Switches_ALPSALPINE-SKRPADE010_C127488.html

optoisolator: https://www.digikey.com/en/products/detail/liteon/6N138S/1969181?s=N4IgTCBcDaIIwDYAMBaOB2AnOlA5AIiALoC%2BQA

credits

Gowin Kicad library: https://github.com/devbisme/KiCad-Schematic-Symbol-Libraries

USB-C connector: EasyEDA library for this product: https://lcsc.com/product-detail/USB-Connectors_XUNPU-TYPEC-304J-BCP16_C2835315.html Converted to KiCad with this tool: https://github.com/RigoLigoRLC/LC2KiCad