DECUS-8-152a was a compiler for music files. The format of these files is more primitive than the files for the later Wilson music compiler: Input apparently begins with an asterisk, followed by a character whose least significant 2 bits determine the amplitude bits of each subsequent output note. After an asterisk directive, a variety of others are allowed: A dollar sign triggers the output of the compiled data in BIN format, suitable for loading over the player. An open pointy bracket ('<'), followed by a two digit octal number, sets the LCO origin, and records the number of notes to date at that address. An close pointy bracket ('>'), followed by a two digit octal number, sets the LCC origin, records the number of notes to date at that address, and increments NLOOP. An uparrow ('^') sets the DAMP bit in the next note. The most complicated thing that can follow is note input: [ABCDEFG] initiate the description of a single note. 'R' seems to designate a rest. The notes set the FREQ0 bits of an output word, while a rest has a FREQ0 of 0. Notes may be followed by [123], which I think choose the octave by bumping FREQ0 by 2 table entries or 4. After the [123], an 'S' will bump FREQ0 by 1, pointing to the "sharp" version of the note. A '/' indicates the end of the frequency information, and a transition to length information. Rests, unlike notes, have an amplitude and frequency of zero. Amplitude is cached, and restored by ??. Notes and rests must be followed by [EHQSW] to set a duration. This may be followed by dots ('.') to increment the duration. Each note is represented in the output file by a word, formed from the length<<5, the frequency, the amplitude, and the DAMP bit.