sheets

Sheets Directory

This directory contains music sheet files in .txt format. Each file represents a different piece of music that can be played by the QUTy board.

Validation Rules and Creating Your Own Sheets

Each sheet is a .txt file that must follow a set of rules to build successfully. Each sheet must contain blocks, which can be either a setting block or a bar (in this context, 'bar' refers to actual bars in music theory). Music knowledge isn't mandatory but will definitely help 😄.

Setting Block

A setting block follows JSON's syntax closely. It is text enclosed with curly brackets {} with setting fields separated by a commas ,, but must all be in a single line. Setting fields are case-sensitive and are key-value pairs separated by an equal sign =. These are the valid key-value pairs of a setting field:

• BPM: Beats Per Minute is two positive integers separated by a /. The first number is the desired BPM value, and the second number is the beat value. Valid beat values are: 1, 2, 4, 8, 16, and 32. The beat value can optionally have a . to indicate that beat value is a dotted note. Not all possible combinations of BPM and beat values are possible, learn why here.
• tsig: Time signature is two positive integers separated by a /. The first number is the number of beats per bar (a.k.a beats per measure), and the second number is the beat value. Valid values for beat value are: 1, 2, 4, 8, 16, and 32.
• anacrusis: Anacrusis represents whether the next bar should have its beats validated. By default, all bars must have the right number of beats based on the current time signature. To declare the next bar an anacrusis bar, set the value to True.
• skipbars: The number of bars to skip processing.

Here's an example of a setting block: { BPM=100/4, tsig=4/4, anacrusis=True }

Why Some BPM and Beat Value Combinations aren't Possible

Some BPM and beat value combinations aren't posssible because of the hardware limitation of the QUTy's TCB. The QUTy uses an ATTINY1626 microcontroller which has a 16-bit timer TCB. Therefore, small BPM values are limited to the TCB's maximum Capture Compare (CCMP) value which is 65535. Examples of the smallest possible values are 64/4 and 128/8 that is 64 BPM with beats as quarter notes and 128 BPM with beats as eighth notes. Any equivalent BPM lower would result in an error.

Bar

Bars represent actual bars in music theory. A bar contains musical elements separated by spaces, enclosed in square brackets [], and must all be in a single line. Covering every possible musical element is challenging, so I have decided to limit the scope to three elements: notes, rests, and tuplets. Each bar can have any number of elements as long as it follows each element's rules and the beats add up to the current time signature.

Note

A note follows the structure {note}-{duration}-{additionals}.

• note can be A, B, C, D, E, F, or G, optionally followed by # or b (to represent sharp or flat, respectively), and an octave number. The octave number must be an integer from 1 to 8.
• duration is either 1, 2, 4, 8, 16, or 32, representing the fraction of the note. That means 1 is a whole note, 2 is a half note, 4 is a quarter note, and so on.
• additionals is one or more characters representing additional attributes for the note. The possible characters and what they represent:
  • .: dotted note
  • @: fermata (in this project, the note is played twice its original duration without affecting beat calculation)
  • <: beginning of a slur
  • >: end of a slur
  • s: staccato

Note examples:

• A4-4: A quarter note playing A on the 4th octave
• C#5-8: An eighth note playing C# on the 5th octave
• D6-4-.: A dotted quarter note playing D on the 6th octave

Rest

A rest follows the structure *-{duration}. Just like durations for notes, it represents the fraction of the rest, with possible values being 1, 2, 4, 8, 16, and 32.

Rest examples:

• *-1: Whole rest
• *-2: Half rest
• *-4: Quarter rest

Tuplet

A tuplet follows the structure {grouping}:{number of regular notes}:{duration of regular note}({element1}_{element2}_{element3}_...).

• grouping is an integer representing the typical number of notes for the tuplet. For example, a 3 represents a triplet, a 5 represents a quintuplet, etc.
• number of regular notes is an integer representing the actual number of regular notes.
• duration of regular note is an integer representing the duration (in fractions) of regular notes.

In this project, all elements within the brackets () are separated by underscores _. The beats of all the elements must add up to grouping * duration of regular note. However, the actual beats is number of regular notes * duration of regular note. Elements can only be notes or rests, but not tuplets themselves.

Tuplet examples:

• 3:2:4(C4-4_D4-4_E4-4): Three quarter notes playing C4, D4, and E4 in the span of two quarter notes
• 5:4:4(F4-4_G4-4_A4-4_B4-4_C5-4): Five quarter notes playing F4, G4, A4, B4, and C5 in the span of four quarter notes
• 3:2:8(C4-16_D4-16_E4-16_F4-16_G4-8): Four sixteenth notes C4, D4, E4, and F4 and an eighth note G4 in the span of three eighth notes.

Additionally, you can optionally create a file whitelist (without extensions) and on each line, give the name of the files (excluding .txt) that you want to be processed. If the file isn't present, then all the .txt files in this directory are processed.