IBM System/370 Model 148 explained

IBM System/370 Model 148
Manufacturer:International Business Machines Corporation (IBM)
Family:System/370
Discontinued:November 1, 1983
Memory:One or two megabytes of high-density integrated monolithic processor storage
Website: IBM Archives

The IBM System/370 Model 148 (and the Model 138[1]) were both announced June 30, 1976[2]

Not only were they both more powerful and better in price/performance than the IBM System/370 Model 145 with a 3145-3 CPU and the IBM System/370 Model 135 with a 3135-3 CPU, respectively, but lower in price.[3]

The 148 and 138,[4] both of which were withdrawn November 1, 1983, were marketed as followups for those wishing to upgrade, respectively, their 370/145 and 370/135 systems.

Expanded capabilities

The 148 had four times the reloadable control storage of the 145,[5] enabling or enhancing features such as:

The 3148 (and the 3138) had a built in service processor, aka known as an IOC, this service processor could directly attach a 3203 printer. The IOC also drives an IBM 3277 display console, whereas the older 3145 used an IBM 3215 typewriter console.

A new model of the IBM 3203 printer family, the Model 4, was announced. Rated at 1200 lines/minute (LPM), it was intended to provide already-available 1200 LPM printing, but in a more compact form.

Field upgrades

Sometimes known as in-the-field upgrades,[8] this is a capability that even recently was not universal.[9]

IBM could upgrade a 370/145 that had been field-upgraded to a 145-2, resulting in a 145-3. This was a major accomplishment, compared to what is known as a "forklift upgrade" out with the old, in with the new, often consuming valuable time.[10] [11]

Marketing considerations

An industry research firm said "may be described as early 380s programmed to act like 370s"[12]

See also

Notes and References

  1. Web site: System/370 Model 138. IBM Archives. 23 January 2003. IBM.
  2. Web site: System/370 Model 148. IBM Archives. 23 January 2003. IBM.
  3. $350,000 for a 138 having 500K of memory, vs. $721,500 for a 135-3 with 500K - less than half the price!
  4. described as "medium-powered System/370 computers" News: . I.B.M. Cutting Prices 20% on 2 Computers . March 2, 1978.
  5. 128K vs. 32K
  6. a microcode-based feature that allowe for faster execution than a software-only approach.
  7. up to 20% for OS/VS1, up to 55% for VM/CMS.
  8. "Is it possible to upgrade a bCX1-R to a bCX1-CR in the field? (upgrade router to controller / router)" - http://buildingskb.schneider-electric.com/view.php?AID=7836
  9. "I am in the early stages of designing the TMS320F28377S into a new product and I would like to build in the field upgrade capability..." - https://e2e.ti.com/support/microcontrollers/c2000/f/171/t/477654?Firmware-upgrade-in-the-filed-TMS320F2837xS-Delfino-Microcontrollers
  10. Web site: How to overcome the infamous forklift upgrade challenge Computerworld . www.computerworld.com . dead . https://web.archive.org/web/20160419032058/http://www.computerworld.com/article/3058252/data-storage/how-to-overcome-the-infamous-forklift-upgrade-challenge.html . 2016-04-19.
  11. Web site: Definition of forklift upgrade.
  12. News: Computerworld. IBM 370/138, 148 Really 'Early 380s'? Users May Have Jump on Upgrades. July 5, 1976 . 2.