# CPU280

## Introduction

The CPU280 is a single-board ECB-interface computer based on the Z280 microprocessor from Zilog, designed and originally manufactured by Tilmann Reh in the early 1990's. The CPU280 runs the Z280 in the Z-BUS mode with a 16-bit data bus. 512KB, 1MB, 2MB, or 4MB of dynamic RAM can be installed. The system boots to CP/M+ from EPROM. The CPU280 was one of the very few hobbyist-buildable Z280 CP/M computers ever made. RBC forum member fritzeflink maintains an archive of information about the CPU280 at his site http://oldcomputers.dyndns.org/public/pub/rechner/zilog/z280/index.html.

Late in 2016, RBC forum member lowen contacted Tilmann Reh and obtained permission to have a new run of boards made. Tilmann very graciously provided the manufacturing files as well as all necessary documentation and source code to rebuild the system, and lowen was able to get a beta run of ten boards made and distributed to several beta builders. RBC forum member Wayne W developed a build setup to rebuild the EPROM images and floppy disk images and set up a github at https://github.com/wwarthen/CPU280 for distribution and development. Several boards were successfully constructed using the beta run, and lowen had another ten boards fabricated. In spring 2018, another ten boards were run.

Tilmann Reh has given blanket permission for unmodified redistribution of the CPU280 files. Tilmann requests notification if the design is modified. Quoting his emailed permission, received by Lowen on 1/10/2017:

For me it's OK to distribute all of the CPU280 stuff (including the gerber files, the PDFs and the software) freely - as long as the design is not modified without my expressed permission.

The original design files in Eagle .BRD format (CPU280-EAGLE.zip ) are available as well. Here is what Tilmann has to say about the way Eagle was used in the early 1990s:

Take care that in the 90s, there was no schematic editor in EAGLE. Instead, i just drew the schematic with the board editor. So now you need to edit both files to keep them synced. (I include the “schematic” file so you can update your documentation/PDF according to the patched PCB.)

So the schematic is also a .BRD file and was drawn in the layout editor of Eagle.

## Hardware Documentation

Board and Schematic: :boards:sbc:cpu280:cpu280_hardware-manual_en.pdf

Manufacturing Files: :boards:sbc:cpu280:z280-e5-gerber.zip

KiCAD Files: Tilmann's original Eagle .BRD files are: :boards:sbc:cpu280:cpu280-eagle.zip Translation to KiCAD is not planned at this time; volunteers to do this are welcome!

## Build Information

<Include thinks like parts lists, BOMs, test software, notes from the board designer, etc in this section.>

Please use this space to add any notes/comments on this board that don't fit into the above sections. (Periodically, these comments may be re-arranged to be better incorporated into a new revision of the wiki page.) Please sign your comments using the wiki “Insert Signature” feature! — Andrew Bingham 2016/02/27 13:01

Nothing was found.

## File List

cpu280-eagle.zip61.9 KiB2018/06/26 09:00
cpu280-v1.20.1.zip684.0 KiB2017/05/26 14:21
cpu280-v1.20.2.zip1.4 MiB2017/08/01 00:22
cpu280_hardware-manual_en.pdf595.2 KiB2017/05/26 13:34
cpu280_software-manual_en.pdf395.4 KiB2017/05/26 13:34
jcoffman-1.jpg149.1 KiB2017/05/26 14:23
jcoffman-2.jpg189.8 KiB2017/05/26 14:23
lro-board-201612-1.jpg6.0 MiB2017/05/26 14:23
reh-cpu280-lro-2016-1.jpg4.9 MiB2017/05/26 14:23
reh-cpu280-lro-2016-web.jpg106.2 KiB2017/05/26 14:17
wayne-w-1.jpg1.8 MiB2017/05/26 14:23
z280-e5-gerber.zip55.0 KiB2017/05/26 13:33
z280_reh.pdf1.4 MiB2017/07/05 15:38