A small, extensible Intel 8086 based computer system.
Some boards are made with Eagle but then I switched to KiCad because my Eagle License covers only 2 layer boards and I don't like their new licensing model (it's too expensive for hobbyists). Schematics and layout are contained in the folders Eagle and KiCad.
First revision of the system backplane with 6 slots and a power connector.
Second revision of the backplane. Has 7 slots and two power connectors (one of them USB-C).
RAM board with 512 KB SRAM.
A 16x2 HD44780 based LCD can be mounted to this board. Also contains some LEDs for important signals.
Information board with LEDs for the busses and all important signals.
First revision of the CPU board, contains socket for an Intel 8086 CPU, ROM and other important system chips:
- Intel 8259 interrupt controller
- Intel 8254 timer
Second revision of the CPU board where I replaced most of the logic chips with an Altera CPLD. Also contains 1 MB SRAM so the external RAM board is not needed.
Simple graphics card with 128 KB SRAM and VGA output. Supported modes:
- text mode 80x25 characters, 256 colors (resolution 640x400 pixels)
- 320x200, 256 colors
- 320x400, 256 colors
- 640x200, 256 colors
- Slots for SD and MicroSD cards. Simple SPI controller implemented in an Altera CPLD.
- PS/2 keyboard connector
- RS232 connector
- I²C controller with a RTC module, BMP sensor module and EEPROM connected.