The Eclipse MV/8000 was the first in a family of

32-bit In computer architecture, 32-bit computing refers to computer systems with a processor, memory, and other major system components that operate on data in 32- bit units. Compared to smaller bit widths, 32-bit computers can perform large calculati ...

minicomputer A minicomputer, or colloquially mini, is a class of smaller general purpose computers that developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, ' ...

s produced by

Data General Data General Corporation was one of the first minicomputer firms of the late 1960s. Three of the four founders were former employees of Digital Equipment Corporation (DEC). Their first product, 1969's Data General Nova, was a 16-bit minicompute ...

during the 1980s. Codenamed ''Eagle'' during development, its architecture was a new 32-bit design backward compatible with the previous

16-bit 16-bit microcomputers are microcomputers that use 16-bit microprocessors. A 16-bit register can store 216 different values. The range of integer values that can be stored in 16 bits depends on the integer representation used. With the two ...

Eclipse An eclipse is an astronomical event that occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three c ...

series. The development of the computer and the people who worked on it were the subject of Tracy Kidder's book '' The Soul of a New Machine''. The MV/8000 was succeeded by the MV/6000, MV/8000-II, MV/2000, MV/2500, MV/4000, MV/10000, MV15000, MV/20000, MV/30000 and MV/40000. Later models such as the MV/40000 were SMP systems with hot-swappable components. The Eclipse MV was a 32-bit CISC architecture with a 4 GB address space. The 4 GB address space was divided into eight rings of 512 MB each with a privilege mechanism mapped onto the rings. The outermost ring, ring-7, was the least privileged. The inner-most ring, ring-0, was the most privileged. The AOS/VS operating system supported the notion of lightweight "tasks" as well as processes. A single process could start various tasks that would all share a global address space (similar to modern "threads"). Tasks were very easy to use from Data General's FORTRAN compiler, and allowed faster

context switch In computing, a context switch is the process of storing the state of a process or thread, so that it can be restored and resume execution at a later point, and then restoring a different, previously saved, state. This allows multiple processe ...

ing than using full processes. One could also start subtasks, using so-called "Son" batch process. This was done using the CLI (Command Line Interpreter). It resulted (de facto) in an online batch process. This process would, however be killed as soon as the user would log-off. The MV/8000 had only two "true" batch processes, as not to frustrate the online processes. The "plus" of the online batches was that they ran with the same priority as the normal online processes.

References

Minicomputers

Eclipse MV/8000 The Eclipse MV/8000 was the first in a family of 32-bit minicomputers produced by Data General during the 1980s. Codenamed ''Eagle'' during development, its architecture was a new 32-bit design backward compatible with the previous 16-bit Eclipse ...

32-bit computers {{mini-compu-stub

See also

References