Highly Liquid UMR-2

I did a 1st batch of Highly Liquid UMR-2 interfaces a couple of months ago with great success.
I’m running the 3rd batch right now.
UMR-2 is the only way to add MIDI to Yamaha CS01 and VSS30 as well as the Casio SK series sampling keyboards.
I also successfully installed it in Juno-6 and Polysix.
UMR-2 is no longer manufactured by Highly Liquid but they made it open source and everything needed to make it is available on Highly Liquid website.

That’s cool!

I don’t need one of these, but if you ever fancy doing a batch of his MIDISpeak boards, I’d be interested.


Interesting. I’ve been thinking about using UMR-2 to midify a (crappy but nice) old Yamaha PortaSound PSS-460.

Hey Modulart,

I’d be interested in entering a new run of UMR2.
It’s been a long time since I wanted to midfy my modded Boss dr-110.

What’s the price and shipping condition on your batch?


Paulus or anyone interested in a prebuilt UMR2 or just a PCB, please PM me.

Bjarne, UMR2 should work with your PSS.

Toneburst, if at least 10 guys are interested in MIDIspeak I can do a batch.

That’s great you are making these available! How about the MIDIWidget?

I ordered a round of boards myself for some synths I’ve acquired secondhand. How are you getting on with programming the microcontroller? Are you using the cradle pcb available on the github or some other method?

I program the PIC using a Pickit3 and a homemade board powered by a 5V regulated AC adapter.

Regarding MIDIwidget, like MIDIspeak if at least 10 guys are interested I can do a batch.

CometBoogers, here is a picture of the setup I use to program the UMR2’s PIC.

It does not look much but it works very well.

It’s awesome that you are making the UMR2s for those of us who are less gifted with a soldering iron!
Does anyone know if the “documented installs” information that used to be on the Highly Liquid forum for the UMR2 still exists anywhere? There must have been over 100 documented installs on different model instruments - I added a few yamaha models myself. I’ve messaged Highly Liquid but no response. Such a shame if it’s all the info has been lost.

I have backed up a few of them.
If interested, let me know I’ll put them online.

Hi, yes please! I’m interested in doing a Casio SK1, SK5 and Yamaha PSS 470. Do you have the matrix arrangements for any of them documented? I posted the configuration for a PSS 270 and 280 on the HL forum years ago, and I’m guessing the 470 is going to be exactly the same but I never documented my installs anywhere but on the forum! Lesson learnt - never expect a website to stick around forever.

I have only the SK1 and SK5
sk1_umr2.pdf (915.6 KB)
sk5_umr2.pdf (729.4 KB)


hi . do you have video with your umr-2 ?

Hi there,
Im having trouble flashing my UMR2. Im using a Pickit3 with the MPLAB IPE hooked up like shown in the Github. Supplied with a regulated 5V. Programming keeps failing.
Which software are you using to flash the hex to the pic? Are there any settings I might be missing?

I use MPLAB IPE too and it works well.
May I ask you where you got the UMR-2 from ?

Can you upload a picture of your set up ?

Thanks so much, that’s awesome! Hope to have enough cash squirreled away next month to make a purchase from you.

You’re welcome.
I have uploaded all the guides I backed up on my website here:

Hi, is your third batch sold out already?
I have cs01 which I would like to midify.