Grant Searle helped me a lot in the early days of this project with some critical MK14 related information. His website contains a scan of the SC/MP datasheet and full instructions to build your own Jupiter Ace - http://home.micros.users.btopenworld.com/
Retro-computing is alive and well in Europe too. Bruno Vivien recounts his tale of bringing his early 1980s DAI system back to life. His site contains a copy of the INS8154 datasheet. His assistance was invaluable in getting the MK14 reproduction ready to go for PCB layout - http://perso.wanadoo.fr/bruno.vivien/DAI/index.htm
Local copy here, since it looks like AOL pulled the hosting on the above link.
Tasm is a flexible assembler that with Paul Robson's SC/MP data file can be used to cross-assemble SC/MP code on a PC. The latest version (3.2) fixes some important bugs in the earlier version that can be found on Paul's website. http://home.comcast.net/~tasm/