{"id":597,"date":"2019-10-13T10:38:57","date_gmt":"2019-10-13T15:38:57","guid":{"rendered":"https:\/\/www.computercollection.net\/?page_id=597"},"modified":"2021-05-15T18:23:54","modified_gmt":"2021-05-15T23:23:54","slug":"micro-ibm-mainframes","status":"publish","type":"page","link":"https:\/\/www.computercollection.net\/index.php\/micro-ibm-mainframes\/","title":{"rendered":"Micro IBM mainframes"},"content":{"rendered":"\n

I have a couple of IBM’s microcomputer-based implementations of their mainframe architecture, plus an IBM XT\/370 card set that does not work (it has a bad M-Card).<\/p>\n\n\n\n

IBM PC XT\/370<\/a><\/h2>\n\n\n\n

One of my two working “mainframes” is an IBM PC XT\/370. The XT\/370 is a PC XT (or, equivalently, a PC with the 256KB mother board and a hard drive), with the PC XT\/370 card set and, somewhat optionally, an IBM 3277 emulation adapter. <\/p>\n\n\n\n

The PC XT\/370 card set comprises two cards: the processor, or P-Card and memory card, or M-Card.<\/p>\n\n\n\n

My PC XT\/370 did not start out life as an XT\/370. Instead it was “cobbled together” (before I acquired it), using an IBM PC\/XT with the requisite 256KB of memory on the mother board and the X\/370 card set which I acquired separately in 2013. It also has a 3rd-party 20MB Seagate hard disk with its own adapter, and a 3.5″ floppy diskette.<\/p>\n\n\n\n

It supports special IBM software, VM\/PC that has a somewhat cut-down version of the IBM VM Control Program (CP) and Conversational Monitor System (CMS). <\/p>\n\n\n\n

IBM P\/390E Card<\/a><\/h2>\n\n\n\n

My other “mainframe” is a PC with an IBM P\/390E card. This PCI card is capable of acting as an IBM 370 mainframe or as a S\/390 mainframe. It is fully capable – it will run the “stock” IBM operating systems.<\/p>\n\n\n\n

Ordinarily this card would be installed in an IBM PC Server 330. Not having one of those handy, I originally used a similar era Pentium II based computer<\/a> – the same one that I use for capturing floppy disks – but running under OS\/2 in this case.<\/p>\n\n\n\n

In 2021, I replaced the hard drives on my Pentium II with SSD’s. Running OS\/2 on an SSD is reminiscent of the old cartoon that showed MVS as a turtle, with a snail labeled IMS on its back (“Wheeeeeeeee”). You can read about this adventure here<\/a>. This first set of photos shows the card, and my original Pentium II setup.<\/p>\n\n\n\n