8088 Mother Board Project

The Mother Board

This project is focused on creating a completely modular system to allow the user to customize their system with the features they want.

The Mother Board features

  • 8 MHz Clock

  • Configured in Minimum mode

  • Address latches

  • Data Transceiver

  • Interrupt disable jumpers

  • 8 pin headers to plug in the system memory and IO devices.

1MB ram

Full 1MB Used for prototyping on the 8088.

  • 2 - 512K ram

32K/64K ROM

The EEPROM is build around is a 5 volt byte alterable EEPROM. This means that you can write to it as if it was RAM sort of. So to protect your code and life of the chip I have included a write protect feature. You upload your code with the SPI adapter, then you can remove the adapter and run the mother board as a stand alone project.

This will only be needed if your wanting to run your project independent of an SPI device (Raspberry Pi, Arduino ). When and if I create a USB card and Video card you can burn your bios to a Rom and eliminate the need to always have the SPI Adapter and SPI master computer.

  • 2 - 32K Sockets, You can mix and match. 32K ROM/32K RAM or 64 KROM

  • Write Protect Enable/Disable jumper.

  • Address 0xF0000 / 0XF8000

SPI Adapter

This is used to interface with the project from a SPI master. Currently can upload code from Arduino or Raspberry PI. The system is capable of booting DOS using a Raspberry PI. The RPI acts as the Video, Keyboard, Timer, and Drives.


  • Hold system bus

  • Resest the system

  • Read/Write the full 1MB of the 8088's Ram

  • Read/Write all 64K of the 8088's IO ports

  • Future uses ............. Writes to the 8088 Rom

Connecting the SPI Adapter to Raspberry PI

  • SCLK - GPIO 11 Pin 23 connects to SCK

  • CE0 - GPIO 8 Pin 24 connects to CS

  • MOSI - GPIO 10 Pin 19 connects to SI

  • MISO - GPIO 9 Pin 21 connects to SO

  • Any Ground Pin connects to GND

  • Pin 2 5+ if you are powering the 8088 PCB with the Raspberry PI

Connecting the SPI Adapter to Arduino

  • SS – digital 10 connects to CS

  • MOSI – digital 11 connects to SI

  • MISO – digital 12 connects to SO

  • SCK – digital 13 connects to SCK

  • GND's are connected

  • 5+ if you are powering the 8088 PCB with the Arduino

Programmable Peripheral Interface 8255/71055

  • Address 0x0378 or Address 0x0278 (all 16 address are lines fully decoded)

  • 3 - 8bit ports (24 IO pins)

Programming Interrupter Controller 8259/71059

  • 8 IRQ pins

  • Address 0x0020 (all 16 address are lines fully decoded)