to16 - nsauzede/cpu86 GitHub Wiki

Thomson TO16 recreation

How to recreate a stripped-down version of the Thomson TO16 PC on a cheap FPGA ?

TO16 PCM specifications

  • Date : 1986-87
  • CPU : Intel 8088 or AMD P8088-1 @4.77MHz/9.54MHz
  • OS : MS-DOS 3.21
  • RAM : 512kB expandable to 768kB
  • VIDEO : Plantronics Colorplus => CGA with more colors/resolutions
  • VRAM : 32kB
  • ROM : 64kB (bios)
  • Modem : 2400 bauds

FPGA design

  • CPU : CPU86 core @5MHz
  • RAM : use 8MB SDRAM @100MHz as ~1MB SSRAM : 00000-9FFFF, A8000-FBFFF
  • VRAM : use 32kB (0x8000) blockram : A0000-A7FFF
  • ROM : use remaining ~16kB (0x4000) blockram as BIOS : FC000-FFFFF