IBM 360 display

floor3 left


IBM 360 Front Panel Consoles

On early computers program control was still partially under manual control. Much debugging could also take place. Programs could be stopped, executioin could be stepped instruction by instruction, or program control be switched to other memory locations and restarted there. The contents of all registers, any memory cell, and the status of input-output channels could be displayed by the operator.
On the Triplex FAA 9020 component computers could also be switched off-line for repair while the remaining processors still handled Air Traffic Radars and flight controller displays.
In emergencies a red pull switch stopped everything, requiring several engineers to spend many hours to check and restore the systems.

IBM 360 model 50 Front Panel as used at Stanford for the ACME project 1966-1974 [Photograph courtesy of John Falk].

Since the data path of the 360-50 was 32 bits (4 bytes), the displays and entry switches were 32 wide. The 360 series had only a 16-bit address, and used one of 16 base registers to get the working 24-bit address. (A HREF="">More [Prof. Richard Fox at U-Texas].
Such machines were also used as part of the FAA 9020 system, see the last console picture.

IBM 360 model 65 Front Panel

[Photograph courtesy of John Falk]. Since the model 65 had a 64-bit data path setting registers now required 64-switches.
A model 360-65 was used as the primary machine for academic and operational computing at The Stanford Computation Center, 1966-19xx. Its successors were in use until December 2003.

IBM 360 model 67 Timesharing Console.

Did this machine model ever replace Stanford's IBM model 65 at the Stanford Computation Center?>

IBM 360-9020E FAA custom model Front Panel, on display at Stanford's Computer Science building. [Gio / NBA]

IBM 360-40 Front Panel [CMHC]

This panel was returned to the CMHC in July 2002.

In August of 2003 we obtained the main control panel of the FAA 360-9020E Triplex Computer from New Beginnings Antiques [NBA]. This control panel was used to manage a system containing 3 Computing Elements (actually 360 model 65 computers), and 3 Input-output control elements (actually 360 model 50 computers).
More photographs this installation will soon be posted.
Information about the FAA 360-9020E Triplex Computer.

General Background

The IBM/360 architecture was intended to cover the range from modest to large systems, and data-processing as well as scientific computation. The principal designers were

The 8-bit byte, 32-bit word architecture of the 360 series also popularized the use of 4-bit, hexadecimal digits. Register-base addition allowed memory to exceed the address capability in an instruction. That aspect was initially considered very awkward by programmers, who were used to direct addressability of any memeory cell.
The 360 design influenced greatly later computers: the RCA Spectra, XDS, Ryad, and the Univac 9000, and to a lesser extent the DEC VAX and Intel architectures, still in use today.

Information about the full range of Old IBM Iron.

Information about Stanford IBM Computers.

Stanford Computaion Center

Stanford University obtained an early IBM 360-65, to augment and eventually replace its Burroughs 5500 system. Most computing was centralized and operated by the Stanford Computaion Center, which consisted of a `Campus facility', an operation at SLAC, with eventually an IBM 360-95, and a system running on a 360-50 dedicated to real-time computing in the Medical School, ACME.

A 360-65 was the principal campus computer for Stanford University from 1966 to 197x. Its successor mainframes are still (2003) in use at the Stanford Computation Center, but the latest one is due to disappear in December 2003.

Stanford's 360-65 was intended to be the 360-67 version, running a not yet completed IBM timesharing system, TSS. But TSS never reached its promised level of performance and was used only at few sites, and never at Stanford.
Ed Feigenbaum, director of the computation center at that time: true :"delivered as a 360/65, to be upgraded later"
EAF: I believe this to be the case. We had initially ordered a 67 but, when that was very late, we felt that we needed to "get going", so we ordered a 65 and did Orville and Wylbur software as a gap-filler. In fact, did we ever take delivery of a real 67? I don't know.

Jon Sandelin from Stanford:
**** When I arrived in May 1970, the machine had 3/4 megabyte, and an IBM imposed limit of one megabyte. My task was to bring it to the one megabyte limit. Latter, a company (not IBM) developed a way of going over one megabyte of main memory on the 360/65 series, and we did increase main memory by something like 1/2 megabyte more (do not remember the exact amount).
I recall Stanford hired Rod Fredrickson (from IBM) to implement the time-sharing option, but he left shortly after I arrived, as he apparently did not get along with the Computer Center Senior Management. Jim Moore would know the gory details.

gio: Rod Frederickson had been before at UC Berkeley, heading the compution services for Prof. Sidney Lamb's Machine Translation Project in the early 1960's [gio]

Stanford Medical School

to come.

IBM 360 Components

SLT Logic Module text [CMHC]

See also

IBM 360 Core Memory Planes [IBM] (1964)

Previous display Next photo Floor down Floor up All the way back