to use various modules (sold by VEB Mikroelektronik Mühlhausen) or load software from tape, thus allowing programming in Forth and Pascal. The operating system was CAOS ("Cassette Aided Operating System"). It was a simple monitor where one could run different "system services" like LOAD (load a program), JUMP (into extension module ROM), MODIFY (memory cells) or BASIC (if it had been built into the ROM or had been loaded from tape). New commands could be added to the menu by magic numbers (standard: 7F 7F 'commandname' 01) anywhere in the memory space. In the last years of the GDR, a floppy attachment ("tower"-style, too) was produced. It featured a 4 MHz CPU and a 5¼" Floppy drive (you could have up to four of them). These (literally: the U 880 A in the attachment did) were able to run CP/M, which was called MicroDOS. (One had to JUMP from the base system to the floppy system and boot from a floppy—another CAOS or MicroDOS). There was also a disk extension mode for CAOS. Hobby projects There were a lot of different projects for the KC 85: a new keyboard (The original being extremely poorly manufactured) RAM disk interfaces (V.24 and others) text systems; WordPro actually featured 80 characters per line mode (4 × 8 font) connection to electronic typewriters (like the GDR-product "Erika S 3004") as keyboard and printer (but dot matrix emulation was very slow) programming language BASICODE (a special BASIC dialect); BASICODE-programs were even broadcast by radio References External links Homepage for GDR-Kleincomputer KC-Club Homepage KC-Museum KC 85 of robotrontechnik.de KC85/4 -the modular monster- KC85/4 System Aufbau Bedienung JKCEMU, an emulation for almost all KCs and more written in Java Z80-based home computers Goods manufactured in East Germany Military of East Germany Science and technology in East Germany Computers designed in Germany