Zet - The x86 (IA-32) open implementation

Project maintainers


Name: zet86
Created: Jul 3, 2008
Updated: Nov 4, 2013
SVN Updated: Apr 30, 2009
SVN: Browse
Latest version: download (might take a bit to start...)
Statistics: View
Bugs: 1 reported / 1 solved
Star9you like it: star it!

Other project properties

Development status:Alpha
Additional info:FPGA proven
WishBone compliant: Yes
WishBone version: n/a
License: GPL


The Zet SoC PC platform and processor is an open implementation of the so widely used x86 architecture. This project is being developed using four different FPGA boards: Xilinx ML-403, Altera DE0, Altera DE1 and Altera DE2-115 boards. Currently it's in a very early stage of development and only the 16 bit part is supported. The official website for the project is: Some features of the Zet SoC PC system include:

  • 16 bit Zet processor equivalent to an Intel 80186, running at 25 Mhz (Wishbone compatible)
  • Wishbone ZBT SRAM memory controller addressing 1 Mb of low memory
  • Wishbone flash memory controller for BIOS storage (ROM BIOS and VIDEO BIOS)
  • Video Graphics Adapter in text mode and 640x480,640x350,320x200 16 colors and 320x200 256 colors in chain 4 representation
  • 8253 simple timer, sending interrupts each 18.2 Hz via IRQ 0
  • 8042 keyboard controller sending PC/XT scancodes via IRQ 1
  • UART support as COM1, using IRQ 4
  • Very simple interrupt controller.
  • Flash memory controller for floppy disk storage
  • Compact Flash card controller for hard disk emulation with full read/write support
  • SD card controller for hard disk emulation with full read/write support
  • GPL implementation of a PC BIOS with several services implemented: interrupts 8h, 9h, 10h, 11h, 12h, 13h, 16h, 18h, 19h, 1Ah, 1Ch
Useful links to the project page:


  • 4-Nov-2013. Version 1.3.0 released! We have a new board, the Altera DE2 and the video memory has been placed on SDRAM, making the DE0 able to run Windows. You can see the complete change in the forums post.

  • 10-Nov-2010. Version 1.2.0 released!! A lot of new changes added. Two new FPGA boards now supported: Altera DE0 and Altera DE2-115. PS2 mouse support, new optimized BIOS with shadow RAM, new Zet opcodes added, system timer and speaker, new UART core and a lot of bug fixes!!

    1-Feb-2010. It's time to play games like Dune 2, Gods or Lemmings!! Three VGA graphical modes have been added: 640x350, 320x200 with 16 colors and 320x200 with 256 colors in chained four representation. Some other major improvements have been added: increased x8 SD card access speed, high performance memory controller, wishbone switch and asynchronous bridges added.