This is an unofficial modification of LinnStrument's firmware, with a flexible way of tuning the keys. You can find about LinnStrument and its official firmware from these pages:
https://www.rogerlinndesign.com/linnstrument
https://github.com/rogerlinndesign/linnstrument-firmware
The inspiration and reason for this modification can be found in this post:
https://www.kvraudio.com/forum/viewtopic.php?f=263&t=559271
The original LinnStument has one parameter for setting the row offset, which is good for most use cases. The LinnStrument's total range is mostly limited by the number of rows, because no matter how many columns you have, the keys will be mostly duplicated because each row only shifts a few notes to the left. The default number of shifts (called row offset) is 5, which is fourth tuning like a guitar.
Some people have found ways to use the LinnStrument turned 90 degrees so that they can have more rows. This can achieve a large range comparable to a grand piano. For example, Jesse Washmon's playing piano pieces with LinnStrument:
https://www.youtube.com/watch?v=KdGFXX-kAig
https://www.youtube.com/watch?v=164qLQyt29g
Without changing the firmware, this vertical configuration will need extra software, and will be complex and inflexible, so I decided to modify the firmware. I added a setting called column offset to global settings for this purpose.
This parameter makes it possible to achieve a large range. In addition to the vertical way of playing, it also allows you to use LinnStrument like a Janko keyboard etc.
To install the pre-built firmware, you can use the Updater app from the updater directory. This should upate the firmware safely, saving the settings etc. This is just the official updater app with the bin file replaced with compiled binary from this branch. To distinguish it from the original firmware, I changed the version number to 223.
You can follow these instructions on LinnStrument's support page for compiling the firmware:
https://www.rogerlinndesign.com/support/support-linnstrument-source-code
Notice two additional things for a "safe update":
- From Arduino IDE's preferences, you need to check "Show verbose output during..." for compiling and uploading in order to see where the compiled files are.
- In order to copy the compiled firmware binary into the LinnStrument Updater app, you need to right click on the app, and choose Show Package Contents, and then find the location of the file in Resources directory.
This modified firmware will behave almost the same as the old one if you don't do anything special. I just modified the bahavior of the +7 row offset button to set a new parameter called column offset which will let you use LinnStrument vertically.
To use the vertical mode:
-
Press and hold the +7 row offset button, the slider screen for column offset will appear. Here, set the column offset to 5.
-
Press and hold the +OCTAVE row offset button, the slider screen for custom row offset will appear. Here, set custom row offset to -1.
Turn LinnStrument 90 degrees counterclockwise with the buttons facing you, then you can play LinnStrument with vertical fourth tuning.
If you like to use vertical third tuning or vertical tritone tuning, just set column offset to the desired number (4 or 6).
Notice that with this modified firmware, the +7 row offset button will not work in the old way. It is modifed to have the new function for setting the column offset parameter. If you need fifth tuning, you will need to press and hold the +OCTAVE button and set the custom row offset to +7.
The column offset parameter can also allow you to use some other interesting tunings.
First let's see how column offset works. Let's call the row offset "R" and the column offset "C", then the original fourth tuning can be expressed as "R:+5 C:+1", which means If you go up one row, increase 5 semitones. If you go right one column, increase 1 semitone. Similarly, the usual fifth tuning can be expressed as "R:+7 C:+1". In the original firmware, the column offset is always 1. It was hardcoded and you can't change it. My modification is just to enable you to set this parameter yourself.
With the column offset parameter, you can use LinnStrument in these interesting ways:
- A vertical fourth tuning as used by Jesse Washmon for this piano playing can be expressed as "R:-1 H:+5".
- Vertical thirds tuning can be expressed as "R:-1 V:4". I like to use this one.
- Janko layout can be expressed as "R:1 C:2".
You can try other settings too.
I haven't changed anything about pitch slides, so after turning the LinnStrument 90 degrees, pitch slides will still work in its old way. This means that you need to slide up/down instead of left/right for pitch slides.
This may not be intuitive, but consider that most people will use this vertical way for piano pieces without pitch slides, this might be okay.
If you have questions, suggestions, please file an issue on GitHub, I'll try my best to improve this while I have time.
I hope you find this way fun to use!