SCIOS is the name given to the SC/MP Input/Output System. The version available here is the modified MK14 I/O System which has the cassette interface and the offset calculator added.
This is available in two forms - as a binary image, or as a commented listing which can be assembled with TASM 3.01
SC/MP ROM Assembler Listing for use with TASM
SC/MP I/O System ROM Image
TASM table for use with TASM 3.01 to assemble SC/MP programs
TGEN.C - a program which generates the TASM table