New Board Spin

A project log for 3-Chip Z80 Design

Combining a Z80 retro design with a modern PSoC CPU. 12/04/2019 at 14:250 Comments

There were some things I wanted to add/change on the first rev of the card. Got the PCBs back from PCBs fabrication but haven't assembled the cards yet. This change:

Z80 Bus Expansion Connector
The primary feature added is the 40-pin bus expansion connector which brings out the Z80 bus. Here's the connector pinout:
Most of the signals are directly from the Z80.  Some of them are hard driven from the PSoC and would need to be changed to Open Drain outputs with pull-ups if there was an expansion card attached to this connector. I mostly want the connector to aid in debugging. Getting all those little chip clips on the Z80 pins and making them stay is just too hard. It's much easier to push the female pin from the Logic Analyzer onto a header.

H4 I/O Connector
Also added a 6-pin connector for additional I/O (maybe an RS-232 port?). Pxx are PSoC pins.