Your first question in probably: Why make another Smartport SD hard drive?
The answer is: to finally have a daisy-chainable hard drive, and also free software / open hardware.

BurgerDisk, like the SP2SD, is based on SmartportSD. It fixes two bugs in its firmware (too slow init to be visible when booting from floppy, and timing out on an A2S4100 with Memory Expansion Card), but mostly, it adds a daisy chaining port.

The daisy-chaining part of the firmware is based on SmartportVHD, an abandoned project based on an exotic development board (the Micropendous-A). Its reverse-engineering was eased a lot by the fact the SmartportVHD's firmware is very well-written, and documented. (After unearthing its source and doc, I mirrored it).

Daisy-chaining is optional, there's no need to even solder a female DB19 if the functionality is not desired. In this case, the BurgerDisk firmware is pin-compatible to the SP2SD and SP2SD v2, and can run on these boards - but at the loss of the "boot rotate" button (v1) and LCD screen (v2). Still, it might be useful for people with the same use-case as me: often boot from floppies, and in need of extra storage, with no need to boot on various partitions on the device.

The prototype PCB shown below had issues, so I'm waiting for revised boards to arrive before releasing anything, but it should be a matter of weeks.

I plan on providing an enclosure matching the Unidisk 3.5's (just a bit flatter).

I don't plan on selling those (at least not more than the extra PCBs, Arduinos etc I'll have), but the firmware is licensed under the GPLv3 and the PCB under CC BY-SA. I've chosen those licenses so that both firmware and hardware stay open, and so that anybody has the right to distribute or sell it - as long as sources are provided.

Here are pictures of the first PCB (complete with bodge wires):


And here is a picture of my file manager, listing all the available volumes on a //c + Unidisk 3.5 + BurgerDisk + Disk //c:


I hope it might interest some of you!

You can find the repository on Github: https://github.com/colinleroy/BurgerDisk

Love the concept.

But I'm going to be honest with you. If the 3-D printed case included with the product doesn't look like a Big Mac or Whopper, I think there's going to be massive disappointment. ;-)

Seriously, having the ability to daisychain in a single hard drive product is great. [clap]

>> JDW said:

But I'm going to be honest with you. If the 3-D printed case included with the product doesn't look like a Big Mac or Whopper, I think there's going to be massive disappointment. ;-) Click to expand...

:-D The BurgerDisk name is in memory of BurgerBecky, and also it's fitting because the device will be stackable with other drives :)