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The IBM System/3 (introduced 1969 〔(Original System/3 Product Announcement )〕 discontinued 1985) was a low-end business computer aimed at new customers and organizations that still used IBM 1400 series computers or unit record equipment. It was the first member of what IBM refers to as their "midrange" line and introduced the RPG II programming language. It was essentially an appliance for small business applications. ==Overview== It featured a new punched card format that was smaller and stored 96 characters. Instead of the rectangular punches in the classic IBM card, the new cards had tiny (1 mm), circular holes much like paper tape. Data was stored in six-bit binary-coded decimal code, with three rows of 32 characters each, or 8-bit EBCDIC, with the two extra holes located in the top rows. Cards had room for 128 printed characters in four rows of 32 characters each. IBM System/370s with a proper card reader could also process the new cards. The new cards were about 1/3 the size of the original 80 column cards but held 20% more text data (96 characters). The smaller, and thus lighter card could be processed with faster with smaller equipment and with fewer jams. The system was targeted to smaller businesses who could not afford larger IBM mainframes. Entry models had as few as 4K (4096) Bytes of Magnetic-core memory which retained their stored values even with no power. Many of the original System/3 model 10 units were shipped ''only'' with card reader/sorter/punch I/O and a printer. The most common punched-card device was IBM 5424 Multifunction Card Unit (MFCU) which read, punched, printed on and sorted the new 96 columns cards. Available as ''RPQ''s (special order equipment) to handle 80-column cards were the IBM 2560 Multifunction Card Machine (MFCM) which could read, punch, interpret and sort, and the IBM 1442 which could only read and punch. A smaller (IBM 5203) printer was attached to the main system (see photo, fan-fold paper showing). Later on, IBM offered multiple models of the existing IBM 1403 printer line, which had been originally built for the IBM 1401 computer. In a card-only system, the RPG II compiler was supplied as two phases. The first phase would be booted from one input hopper of the MFCU, and the source would then be read following the compiler. An intermediate form was punched on cards, which were then read by the second phase of the compiler. An executable program deck was then punched. This executable could then be booted ("IPL'ed", for "Initial Program Load") to perform the processing desired. This process could require more than an hour for a significant sized program. For mass storage, the System/3 used the IBM 5444 single-platter disk,〔(System/3 ), IBM engineering announcement〕 roughly the size of a large pizza; initially each platter held 2.5 MB of data. Standard configuration for storage was one or two fixed disks, each in a separate pull-out drawer, which typically held the operating system and user-developed programs. Additionally, each fixed disc could have a removable cartridge disk attached; these typically contained the data-files associated with various applications, for example Payroll, and users frequently had a number of them. Thus the low-end systems could support a maximum of 10 MB of online storage (two fixed, 2 removable), although in practice this was very expensive and not common. Offline storage was available with the purchase of an external tape drive which read and wrote standard IBM tape content. System printing was typically via line printers or bi-directional dot matrix printers. A modified Selectric typewriter was often used as a console. The System/3 came standard with a RPG II compiler, and used a simple job control language called OCL, which was superficially similar to the famous (or infamous) Job Control Language. The System/3 and successor models (System/32, System/34, System/36 and System/38, then the AS/400, iSeries), System i and IBM i are generally referred to as minicomputers or in IBM terminology "midrange systems"—in contrast to IBM's more traditional large mainframes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「IBM System/3」の詳細全文を読む スポンサード リンク
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