UP4 USB volume pedal
What is UP4 USB pedal and how it works? This is a volume/expression pedal based on Arduino. Officially this is a GMLab products but you can also find this on the market under the brand Crumar. GMlab and Crumar is basically the same company but GMlab is a different line of products, mostly DIY and open source.
This pedal, instead of having the classic TRS or TS jack input, it has a USB type "A" plug, so it can be plugged directly to a computer or other devices with a USB type "A" connector because it is active... it's like plugging a mouse or a keyboard. The typical example is when you are running a software on your computer for making music and you would like to have a pedal to control the volume (or another control change). You plug the pedal to your computer, you wait a few seconds/minutes in order to have this recognized by your PC and then it will send MIDI CC like a normal and common MIDI controller. NO DRIVERS ARE REQUIRED. THIS IS CLASS A COMPLIANT DEVICE. Of course you have to setup your software to work with it, a matter that we do not cover on this article because there are thousand of softwares in the market. Please keep in mind that this device is based on Arduino (Leonardo) so don't expect to see a device called "Crumar UP4" or something similar on your system/DAW/software, you will see "Arduino Leonardo" and this is a MIDI device. Sometimes you can also connect UP4 directlt to musical instruments. For example you have a keyboard with a USB type "A" connector on the back that can be used for multiple purposes... if that keyboard/pedalboard/effect etc etc is able to recognize and configure class compliant USB MIDI devices, there's the possibility that this will work. Of course we cannot guarantee this, it depends on the device.
How to configure UP4? It doesn't have any software or editor, simply it has dip switches used for configuration. You have to remove the metal plate in the bottom of the pedal to expose them. Please take a look at the PDF attached. Basically you have 8 DIP switches, based on the position of them you can select the type of CC sent out, the polarity, the scaling and the MIDI channel. Let's say for example that you want your pedal to send linear messages, CC-2 on MIDI channel 6. You have to set the dip switches in this way: n1 down and n2 down (this means linear), n3 up and n4 down (this means CC2) n5 down, n6 up, n7 down, n8 up (this means MIDI channel 6).
How can I check if my UP4 is working as expected? This is quite simple... to narrow down your complicated system and get rid of all software-related problems that could prevent to check, the best thing to do is to just use a MIDI monitor software for MIDI messages, something like MIDI OX. Just plug your pedal in your computer USB port, open MIDI-OX, select your MIDI device, in this case "Arduino Leonardo", open the MIDI messages window called "input monitor" and move the pedal up and down. Do you see the messages? If so, the pedal is working as expected. We also have our own web-based MIDI monitor software that you can use. Just please be sure that your system support WEB API MIDI and please use Chrome. Please note that it doesn't work on iPAD.
You can reach the page here: https://www.gsidsp.com/MidiMonitor/ . Just plug the pedal, select "Arduino Leonardo" in the menu and move the pedal. You will see the MIDI messages going.
APPLE USERS AND LOGIC: please note.
Between the controller and the plugin, Logic uses its own MIDI map: if this one is still active or not properly configured, MIDI messages coming from UP-4 arrive to Logic but Logic is not forwarding them to the plugin.