In part 1 of this series we took a very quick tour through the whole process of designing a product. We will now begin a much more detailed look at designing a Digital Input/Output interface for a Z80 computer.

Someone recently asked me a few questions about design, which got me thinking about writing a series of posts for this website.

I hope to encourage anyone who has considered designing their own retro computer add-on, or indeed a whole system, to have a go. Getting that first professional looking PCB in the post is very rewarding and is relatively cheap.

SC126 Z180 SBC / Motherboard with RomWBW firmware has now been released.

Currently in development is a Z180 motherboard with RC2014 compatible expansion sockets.

I launched my first kit for the Z80Bus today.

I’ve now released my Z180 module set for RC2014, consisting of a Z180 CPU module and a Z180 memory module.

I’ve extended my range of kits designed for RC2014. Here is the current list:

• SC102 – Z80 CTC Module
• SC103 – Z80 PIO Module
• SC108 – Z80 Processor Module
• SC112 – Module Backplane
• SC114 – Z80 Motherboard
• SC116 – 3-slot Backplane

The Z80 CTC Module (SC102) for RC2014 is now available as a complete kit at Tindie.