USB cable for the 1541 and others

You’ve got to be kidding me…

… but of course it’s not a joke. The photo shown above is also not a fake, but really works.

At one end is a normal USB and at the other end a 6-pin DIN connector, which can be used on any Commodore device with the appropriate connector.

For example, the Commodore 1541 floppy drive. The software used is the well-known openCBM Suite.

This cannot work at all

Of course you can’t just solder the 4 wires of the USB cable directly to the 6-pin DIN connector. OK, of course you can, but it won’t work 🙂

There is a little bit of magic involved.

How does that work now?

OK, I won’t keep you in suspense any longer. The joke of the whole thing is that I have shrunk the ZoomFloppy once again. Just like I did with my first XoomFloppy, only even smaller.

The external housing was quite nice back then. But the problem was always getting individual housings. Just building a XoomFloppy and an enclosure around it was not possible. Because of the minimum order value from the supplier, you always had to buy several dozen.

So we got rid of the enclosure and put the circuit board directly into the standard DIN connector.


The starting point was my first XoomFloppy at the time. There I had already left out the parallel and IEEE-488 connection.

Theoretically, of course, you could continue to use these and lead them out as cables. But somehow I found that this contradicted the concept.

Many people simply use the serial connection, and such a cable was always intended for them.

The wiring diagram is based on that of the ZoomFloppy:

Interior view

Opening the DIN connector reveals the circuit board:

XoomFloppy Cable

The board is a simple 2-layer design. There are 3 more components on the back, which unfortunately did not find room on the front.

They are all standard components that are readily available. And with the 0402 size, the smallest components are still easy to solder even for ambitious hobbyists.

The USB cable is then connected to 4 solder pads on the back.

The unpopulated board looks like this:

Can it be any smaller?

Yes, I had also made a version that was even a little smaller. However, I had to use multilayers and even smaller components, and the VIAs had to be smaller.

After I uploaded the Gerber files to the usual PCB manufacturers, I dropped the whole thing for cost reasons. The slightly smaller VIAs alone would have driven up the price extremely.

That’s why the circuit board is so big that it just fits into the connector housing. In return, you can get the whole thing at JLCPCB for the standard price of $2.


If there is enough interest, I would take the trouble to upload the whole project to GitHub. Let’s see how many comments come together…

Otherwise, my friends can find all the necessary files for download in the internal area.

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