These development systems used at times Intel 8008, 8080, and 8085 processors, hosted the ISIS-II operating system, and supported editors, cross assemblers, cross compilers, linkers, PROM programmers, and in-circuit emulation tools for all of the Intel products of the time. See http://www.classiccmp.org/hp/mds-800/mds-800.htm
Binaries of Credit have been archived on Bitsavers. See http://www.bitsavers.org/bits/Intel/MDS/MDS_II/8in_SD/