Hello all I can not download anything from this link I always said I try in 2 minutes and I think there are interesting things This page is for Model III but there are also coconut http://www.retrocomputing.net/parts/r/radio/TRS80_4/docs/trs80-sw.htm http://www.retrocomputing.net/parts/r/radio/TRS80_4/docs/trs80-sw.htm