Kp25tk

hwdev: cjs's Hardware Development Repo

Note for developers: Please run Test before committing. But also:

• In order to avoid a lot of spurious changes on dev branches, Test will update renders only if you are commiting to the main branch. On dev branches, if you want to see/test renders, just use the render script directly. Ensure you bring commits to main and run Test there before pushing them and test them on main.
• If you see massive changes to renders in all projects when you run Test, you are probably running a different version of KiCad than normally used with this repo. Check the kicad-version file for changes and, if lower, upgrade, or if higher, discuss with the repo owner.

General Files and Directores

• Test: Top-level test script.
• bin/: Support programs and scripts.
  • bin/render: Given paths to .kicad_sch and .kicad_pcb files, renders PDF and Gerber versions of these to a render/ dir at the same level as the directory containing the sch/pcb files. Run bin/render -h for more details.
  • bin/ghdl-url: Given a path to a file in a repo, return the fully resolved (i.e., not HTTP 302 redirects) GitHub download URL for it. (See the header comments in the file for more detail.)
• kicad-version: The version of KiCad used in the commit.
• kicad-lib: Contains the 0cjs-hwdev KiCad symbol library, mainly vintage parts.

Project Directories

• drom: Ideas for a diode-ROM board.
• floppy-head-protector: PCB-only project to build a template to cut out cardboard head travel protectors for 5.25" floppy diskette drives.
• kp25tk: Configurable 25-key parallel keypad, with additional reset button and slide switch. The primary use is as a hex keypad interface to trainer boards, but it can serve a wide variety of purposes.
• rc6800: Variant of the RC6502 bus design, which is in turn a variant of the RC2014 bus.
• romext-2364: A 2764 EPROM in this board outside the system is connected via a cable as a 2364 ROM in a socket in the system.
• tk85: Projects for the NEC TK-85 trainer board.

Project Files and Subdirectories

Projects generally include the following files and subdirectories:

• REAMDE.md: A description of the project.
• vis/: Original diagrams, photos and other illustrations and visualisations of the project.
• kicad/: The KiCad design files (.kicad_pro, .kicad_sch, etc.).
• render/: Renderings from the KiCad design files, including a PDF of the schematic and Gerbers of the board design. These are usually generated via the top-level render script but may be created manually; see above. (Also see below about viewing board designs.)

Revision Numbers

Project use revisions int the format S-B where S is the schematic revision and B is the board revision within that scheamtic. Either number being suffixed with dev indicates that it's a development revision heading towards that next revision, e.g., 2dev-3 is development towards revision 2 of the schematic. (Revision 0 is always considered a development revision towards revision 1.)

The revision number is separately set and updated (in File » Page Settings…) for the schematic and PCB. If you change the schematic from 2 to 3 you will then manually need to change the PCB to from 2-3 to 3-4dev.

Release versions are tagged in Git with the project name and release, separated by an underscore, e.g. kp25tk_2-1.

Viewing Board Designs

The $PROJECT/render/$PROJECT-jlcpcb.zip contains a subset of Gerbers designed for upload to JLCPCB. This file also serves as a way to view the board design without having to load up KiCad: you can upload this file to any of several web-based Gerber viewers. These include:

• PCBWay viewer: Press the '+' button and upload the ZIP. Provides Gerber layers and 2D top and bottom board views. Saves the uploads so you need not upload again if you come back later.

• JLCPCB viewer: Requires sign-in. Click "Add gerber file" at the middle left of the top page (or at the top of the order page) and then click "Gerber Viewer" at the lower right just below the small renders. provides Gerber layers and both 2D top/bottom 3D board renders.

• NextPCB viewer: Click "Upload Files" and upload the ZIP. Provides Gerber layer views, error checking, and a PDF report download that includes 2D top/ bottom board views.

• Tracespace viewer: An open source viewer that can accept URLs to ZIP files of Gerbers. (This has been re-used by several PCB house websites and others.) Unfortunately, it does not follow HTTP 302 redirects, so it doesn't work with "raw download" links from GitHub; you need to convert them to the githubusercontent.com link with the bin/ghdl-url program. Also, unfortunately, there seems to be no way to specify the download URL in a query string to have it automatically load the data by clicking on a link.

Viewers confirmed not to work with the ZIP file include the Altium 365 viewer. (These may work by uploading the individual files under the render/$PROJECT-gerber/ directory.)