/tang20k-speccy

Primary LanguageGLSL

ZX Spectrum on Tang Nano 20k devboard

Yet another ZX Spectrum clone on Sipeed Tang Nano 20k development board.

The firmware is still under heavy development. Border effects works incorrectly yet.

Implemented hardware

  • HDMI output at 720x576 (49Hz)
  • Analog sound output
  • USB Keyboard
  • Z80 Soft CPU (T80a)
  • DivMMC with ESXDOS 0.8.9
  • Turbosound (2x AY3-8010)
  • Soundrive

How-to make it running

  1. Install openFpgaLoader tool
  2. Upload bitstream into the external flash openFPGALoader -f impl/pnr/tang20k-speccy.fs
  3. Connect USB keyboard (+5V, GND as well as D+, D- signals via 33 Ohm resistors)
  4. Prepare the SD card (FAT32, ESXDOS 0.8.9)

Controls

  • F10 - CPU reset
  • F11 - NMI
  • F12 - Reset

TODO

  1. Refactor a videocontroller, implement it via a classic scheme with the scandoubler
  2. Add i2c RTC and optionally i2c eeprom
  3. Add ESP8266 module support via ZXUNO UART / AY UART or ZiFi UART standard
  4. Add USB mouse as kempston mouse
  5. Add USB gamepad as kempston joystick
  6. Implement more video modes (like Timex hires, ULA+, etc)
  7. Add Tape in/out
  8. Create an addon PCB (motherboard?) for advanced peripherial