Expansion Bus

A project log for Y Ddraig - My 68000 Computer

An expandable 68000 based computer

Stephen MoodyStephen Moody 09/07/2021 at 15:260 Comments

There are 4 expansion slots on the board.

Each slot is using a 64-pin DIN 41612 connector. The connector supply data, address and some common bus signals as well as power to each of the boards.

There are also 2 select signals for each slot, all access for each slot is memory mapped on on the address bus.

One is a 256-byte range that is designed for register access or control and a 1-Megabyte range for accessing data. For example, on the VGA card the control of the card if done through the registers, but if needed direct access to the VRAM can be done through the data range.

The signals for the expansion slot are: