Fully built and tested board for the "Minimal chip count" z80 computer. Original design by Grant Searle This is the 32k version. PCB layout by Jeff Tranter.

Own your own 1980's BASIC computer.

This board has been built on a design by Jeff Trantor all credit to him for the layout, I have added a couple of changes. The RTS line is now connected for hardware flow control and a ground plane added to reduce cross talk etc.

The original PCB Layout (the layout is identical to this one, except for one extra power connector) can be found here:

https://oshwlab.com/tranter/z80-single-board-computer

Also on Github (has a version of BASIC for the completed board)

https://github.com/jefftranter/Z80/tree/master/sbc

The circuit is based on a design (Grant Searle) web site for this board is (also has software):

http://searle.x10host.com/z80/SimpleZ80_32K.html

I have also uploaded a few example programs like startreck, Othello etc to:

https://github.com/coopzone-dc/32kbasicz80

This board will also run FORTH, the Camelforth BootRom by Justin Skists, see last photo showing forth welcome screen.

A real blast from the past, a great bit of fun.

I have built and tested a several of these, This one is surplus to my requirements. It will be provided with the version of BASIC from Grant Searle. It has been tested with various versions of BASIC, they all work fine. for example:

Basic4.7b (Original from Grant Searle web site). 32k version. Provided in Eprom with this board.

Basic4.7m (BASIC with a simple Monitor built in)

RC2014-Basic4.7c (From  Github download)

Hardware features:

1 x Z80 processor clocked at 7.372 MHz.

1 x 32k byte RAM.

1 x 8k byte (ROM), for MS/Nascom Basic 4.7

1 x Serial port. asynchronous, 5-volt with hardware flow control.

1 x FTDI adapter and 6 pin connector

1 x USB to PC cable

1 x Push button reset

1 x expansion connector

This listing is for a complete working system, see photos for more info.

Note: where possible I use reclaimed or NOS parts. This is to help reduce world wide waste and is another form of recycling.

Thanks for looking.