IBM System/360 Model 30

Model 30360/30IBM 2030System/360 Model 30IBM 360/30S/360 model 30
The IBM System/360 Model 30 was a low-end member of the IBM System/360 family.wikipedia
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IBM System/360

System/360IBM 360IBM/360
The Model 30 was a popular IBM mainframe announced in 1964 across the world as the then least powerful of the System/360s – the first line of computers in the world to allow machine language programs to be written that could be used across a broad range of compatible sizes. Along with the 360/40, these were the two largest revenue producing System/360 models, accounting for over half the System/360 units sold. It was the smallest model that had the full System/360 instruction set (unlike the Model 20) and served as a stand-alone system, communications system or as a satellite processor of a larger system.
The slowest System/360 model announced in 1964, the Model 30, could perform up to 34,500 instructions per second, with memory from 8 to 64 KB.

IBM System/360 Model 40

Model 40360/4040
Along with the 360/40, these were the two largest revenue producing System/360 models, accounting for over half the System/360 units sold.
The 360/30 and the 360/40 were the two largest revenue producing System/360 models, accounting for over half of the units sold.

Microcode

microprogrammicroprogrammingmicroprogrammed
emulated by the microprogram.
The IBM System/360 has a 32-bit architecture with 16 general-purpose registers, but most of the System/360 implementations actually use hardware that implemented a much simpler underlying microarchitecture; for example, the System/360 Model 30 has 8-bit data paths to the arithmetic logic unit (ALU) and main memory and implemented the general-purpose registers in a special unit of higher-speed core memory, and the System/360 Model 40 has 8-bit data paths to the ALU and 16-bit data paths to main memory and also implemented the general-purpose registers in a special unit of higher-speed core memory.

Central processing unit

CPUprocessorprocessors
The CPU used an 8-bit microarchitecture with only a few hardware registers; everything that the programmer saw was
For example, even though the IBM System/360 instruction set was a 32-bit instruction set, the System/360 Model 30 and Model 40 had 8-bit data paths in the arithmetic logical unit, so that a 32-bit add required four cycles, one for each 8 bits of the operands, and, even though the Motorola 68000 series instruction set was a 32-bit instruction set, the Motorola 68000 and Motorola 68010 had 16-bit data paths in the arithmetic logical unit, so that a 32-bit add required two cycles.

DOS/360 and successors

DOS/360DOS/VSTOS/360
TOS (Tape Operating System), as the name suggests, required a tape drive but no disk.
TOS/360 (Tape Operating System/360, not a DOS as such and not so called) was an IBM operating system for the System/360, used in the early days around 1965 to support the System/360 Model 30 and similar platforms.

Read-only memory

ROMRead Only MemoryROMs
The microcode was stored in CCROS (Card Capacitor Read-Only Storage) developed in Endicott.

Endicott, New York

EndicottEndicott, NYHenry B. Endicott
The Model 30 was designed by IBM's General Systems Division in Endicott, New York, and manufactured in Endicott and other IBM manufacturing sites outside of U.S.

IBM mainframe

IBM mainframesmainframeIBM mainframe computers
The Model 30 was a popular IBM mainframe announced in 1964 across the world as the then least powerful of the System/360s – the first line of computers in the world to allow machine language programs to be written that could be used across a broad range of compatible sizes.

IBM System/360 Model 20

Model 20System/360 Model 2020
It was the smallest model that had the full System/360 instruction set (unlike the Model 20) and served as a stand-alone system, communications system or as a satellite processor of a larger system.

McDonnell Aircraft Corporation

McDonnell AircraftMcDonnellMcDonnell Aircraft Company
The first delivery of the 360/30 was in June 1965 to McDonnell Aircraft.

Magnetic-core memory

core memorymagnetic core memoryferrite core memory
They vary by the amount of core memory with which the system was offered.

IBM 1401

14011401 computer1401/1440/1460
The two were cosmetically different; the 30-1 looked like other System/360 models, with indicator lamps exposed on the front panel and labeled, but the 30-2 took a retrograde design step, putting the lights behind a stencil, as they had been on pre-360 machines like the IBM 1401.

Microarchitecture

µarcharchitecturecomputer organization
The CPU used an 8-bit microarchitecture with only a few hardware registers; everything that the programmer saw was

Hardware register

registerregisterscontrol register
The CPU used an 8-bit microarchitecture with only a few hardware registers; everything that the programmer saw was

Emulator

Transformer read-only storage

Transformer Read Only Storage
The Model 30 and Model 40 were originally supposed to share the transformer read-only storage (TROS) being developed at IBM Hursley, but CCROS was cheaper to manufacture.

IBM Hursley

HursleyHursley Development LaboratoryIBM Hursley Site
The Model 30 and Model 40 were originally supposed to share the transformer read-only storage (TROS) being developed at IBM Hursley, but CCROS was cheaper to manufacture.

BoPET

MylarPET filmbiaxially oriented PET film
This system used Mylar cards the size and shape of a standard IBM punched-card, so the microcode could be changed using a keypunch.

Punched card

punched cardspunch cardpunch cards
This system used Mylar cards the size and shape of a standard IBM punched-card, so the microcode could be changed using a keypunch.

Keypunch

key punchIBM 029card punches
This system used Mylar cards the size and shape of a standard IBM punched-card, so the microcode could be changed using a keypunch.

Operating system

operating systemsOScomputer operating system