I am a programmer by profession, and one of my hobbies is to reverse engineer file formats, so I looked at the Roland files to see if I could convert them myself. Roland uses their own proprietary format to store songs. Each song is stored in two files, one with extension ".rsc" and one with extension ".rsd". The rsc (Roland Song Context?) file contains the name of the song and other general data about the song. I have not decoded this file completely, but I don't think most of the data in this file is relevant when converting to MIDI. The rsd (Roland Song Data?) file contains the actual song data, and I think I've managed to decode this file completely.
I have written a program (called roland2midi) that will try to convert the Roland files to a ".mid" file. To download the offline version of the program, click here: Offline Roland to MIDI Converter. The program works only from the command line; if you click the link, you will also see a description of how to use it. I have also set up an online version of the program here: Online Roland to MIDI Converter
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