IBM System/360 Model 195 explained

IBM System/360 Model 195
Developer:IBM
Release Date:August 20, 1969
Price:$7–12.5 million
Discontinued:February 9, 1977
Predecessor:IBM S/360 Model 91
Successor:IBM S/370 Model 195

The IBM System/360 Model 195 is a discontinued IBM computer introduced on August 20, 1969. The Model 195 was a reimplementation of the IBM System/360 Model 91 design using monolithic integrated circuits.[1] It offers "an internal processing speed about twice as fast as the Model 85, the next most powerful System/360".[2] The Model 195 was discontinued on February 9, 1977, the same date as the System/370 Model 195.

About 20 Model 195 systems were produced.[3] [4]

Technical specifications

The basic CPU cycle time is 54 nanoseconds (ns). The system has a high degree of parallelism and can process up to seven operations at a time.The system can be configured with 1, 2, or 4 MB of magnetic core memory (models 195J, 195K, and 195L) with a cycle time of 756 ns. A 32 KB cache, called a buffer memory in the IBM announcement, is standard. Memory blocks are brought into cache in units of 64 bytes.

The normal operating system for the Model 195 is OS/360 Multiprogramming with a Variable Number of Tasks (MVT).

Legacy

The Model 195 was later updated as the IBM System/370 Model 195 with the new System/370 instructions and the 370 TOD clock and control registers, but without the virtual memory hardware.[5]

External links

Notes and References

  1. The 360/91 and associated machines. gah. April 20, 2008. hercules-390@yahoogroups.com.
  2. Web site: IBM Archive: System/360 Model 195. IBM. 23 January 2003. June 28, 2017. https://web.archive.org/web/20230729090329/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP2195.html. 2023-07-29. dead.
  3. Web site: Eager Execution / Dual Path / Multiple Path. Mark Smotherman. 15 Model 91's and 2 Model 95's were built. Approximately twenty Model 195's were built..
  4. Web site: Some Reflections on Computer Engineering: 30 Years after the IBM System 360 Model 91 . https://web.archive.org/web/20161221084029/https://pdfs.semanticscholar.org/ceea/f56b486b7290c8638d3781e53de3229efda7.pdf. December 21, 2016. dead. Semantic Scholar . Michael J. Flynn. Michael J. Flynn. December 2, 1997. 5958256. About twenty Model 91s were made, and perhaps an equivalent number of the Model 195..
  5. Web site: IBM 360/370/3090/390 Model Numbers.