I've made an adapter that allows connecting a USB keyboard to E-mu Ultra samplers without the DWAM expansion board.
Required components are a Raspberry Pi Pico, some wires and a USB cable so the keyboard and the Pico's USB port can be connected. There's no PCB, one can be made but it's just four wires between the Pico and the sampler, no external components needed.
Mounting it in the case is left as an excercise to the reader, be careful not to short things out!
The firmware has been tested with a plain Pico, not the wireless version.
Please read the build instructions carefully. Good familiarity with the Pico and electronics is assumed for now. A more approachable solution might become available in the future.DO NOT EVER SO MUCH AS THINK ABOUT PLUGGING THE PICO INTO A COMPUTER'S USB PORT WHILE IT IS ALSO CONNECTED TO THE SAMPLER. Read the instructions carefully.
As of late 2023, a few of these adapters have been built, one by me and some by others who have followed the instructions.
The source code for this is available here.
NO COST - NO REFUNDS - NO PROMISES - NO WARRANTY
(but please e-mail me at dwam@rven.se if you make one!)
Is there a ready-to-use-solution?
No. I released this to the world about a year ago but I don't have a lot of bandwidth for projects, and this isn't so far up my list of priorities. I invite anyone else to make a board for it, though. There isn't much to it.
Will this work in my non-Ultra E-mu?
I only have Ultras. I was unaware previously that there are two versions of the E-mu Classic hardware. The e6400 has the keyboard port on an optional board which isn't the same as the DWAM board for the Ultras, but the keyboard-related hardware looks identitical. As such, I suspect it might work if you connect the Pico to the appropriate pins on the e6400, and have included the pinout in the description. This is untested - please shoot me an e-mail if you try it!
What about all the other features of the DWAM board, could they be brought to USB too?
Yes, they could. I've worked on this on and off but have nothing to show yet.