Plug compatible: Difference between revisions

The original example of PCM mainframes was the [[Amdahl Corporation|Amdahl]] [[Amdahl 470|470]] [[mainframe computer]] which was plug-compatible with the [[IBM]] [[System 360]] and [[System 370|370]], costing millions of dollars to develop. An IBM customer could literally remove the 360 or 370 on Friday, install the Amdahl 470, attach the same connectors from the peripherals to the channel interfaces, and have the new mainframe up and running the same software on Sunday night. Unfortunately, system status indicators for operators of the new system were very different, which introduced a learning curve for operators and service technicians.
Similar systems were available from [[Comparex]], [[Fujitsu]]<ref>"LEAD: andBeating [[HitachiI.B.M. to the punch by one day, Fujitsu Ltd.|Hitachi]]. announced
a series of computers today that ..." {{cite web | |title=Fujitsu Announces Mainframe
|date=September 5, 1990}}</ref> and [[Hitachi, Ltd.|Hitachi]].
Most of these system vendors evenutally left the PCM market.<ref>"Hitachi has been in the mainframe business for 50 years and currently its AP series of systems are sold to major organisations across Japan. Hitachi Data Systems used to sell Hitachi-made IBM plug-compatible mainframes outside Japan but stopped doing so in 2000." {{cite newspaper |newspaper=The Register |date=May 24, 2017