!12Ton helps to compose and analyse music using twelve-tone technique. It is a DOS software, running in graphic mode.
!12Ton was implemented using Turbo Pascal 7. It needs graph.tpu and egavga.obj. You can create the latter one using
binobj egavga.bgi egavga.obj grvtrb
The software was originally a shareware and codier.pas was used to create the file 12ton.miz from _12ton.mi and to put the license holder information therein. Now all these files were removed, as a software in public domain does not need them anymore.
The software was developed by Matthias Kleinmann in the nineties and distributed as a shareware. As of 2023, the author put the software into public domain, as stated in an e-mail conversation. More information in Unlicense.