Author: Chris Lott

262 Articles

USB Adaptor Isolates Multiple Serial Interfaces

October 13, 2020 by 34 Comments

You need a Swiss Army knife of serial communications? Ollie is a compact isolated USB adaptor that provides USB, CAN bus, and two UARTs at logic, RS-232, and RS-485 signaling levels, as well as an isolated power supply.  [Slimelec] has managed to squeeze all this into a package the size of a harmonica.  We like the technique of making the enclosure from PCB material, complete with clearly labeled switch, LED and connector pinout names.

So far, only the compiled firmware is available for this project, but hardware files, and presumably the source code and documentation, are coming soon.

The central themes here are  isolation and flexibility. We can’t find the isolation voltage in the project specifications, but the CANable project on which this adaptor is based provides 2.5 kV galvanic isolation.  A single isolated USB interface is also provided over a standard Type A connector. The four-wire logic-level UART signals are available on a 2 x 7 box header, and are voltage selectable.  The RS-232, RS-485, and CAN signals are on an 8-pin pluggable screw terminal block, or you can use a DB9 connector with a pluggable adaptor board.

Whether you need a troubleshooting aid for field testing, are using CAN bus on your projects, or just want to isolate your expensive computer from sketchy prototype hardware, have a look at this project.

An Up-To-Date Datasette For Commodore TED Series

October 12, 2020 by 4 Comments

Retro computer enthusiast [Steven Combs] documents his adventure building the TEDuino, a modern replacement for the Commodore Datasette which uses an SD card instead of audio tape. He based the design on [Peter Edwards]’s Tapuino project, which was featured by Hackaday back in 2014. [Steven] took the aesthetic design to a new level, and also modified it to work with his Plus/4 and other TED series Commodores.  We are amazed that he was able to design this enclosure in SketchUp, and impressed with the results from his Creality Ender 3. He went to great lengths to match the color and style of the Plus/4, and pulled it off quite well. [Steven] also applied some interesting design features in this enclosure. The PCB modules are snap-fit, the buttons are made as a single piece – not unlike a living hinge. The 3D-printed strain relief for the cable is a nice finishing touch, and we cannot disagree with [Steven]’s sage advice – “Gorilla anything is just cool”.

This is only part 1 of the project. Stay tuned for future improvements, tweaks and embellishments.

Continue reading “An Up-To-Date Datasette For Commodore TED Series” →

Improved Part Searches For JLCPCB Parts

October 11, 2020 by 29 Comments

Finding the JLCPCB component parts library frustrating to navigate, [Jan Mrázek] took matters into his own hands and made an open-source parametric search utility. We’ve all probably wasted time before trying to track down a particular flavor of a part, and this tool promises to make the process easier.  It downloads data from the JLCPCB parts site upon initialization and presents the user with typical selection filters for categories and parameter values. You can install it yourself on GitHub Pages, or [Jan] provides a link to his site.

For the curious, the details of how to pull parts information from the JLBPCB site can be found in the project’s source code.  We like it when a distributor provides this level of access to their part details and parameters, allowing others to sort and filter the parts in ways not originally envisioned by the site design team.  We think this is a win-win situation — distributors can’t sell parts that designers can’t find.

If [Jan]’s name sounds familiar, it should be.  We have written about several of his projects before, two of them are also PCB designer tools ( KiCad Board Renderings and KiCad Panelization ).