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43-454: The B2500 and B3500 computers were announced in 1966. They operated directly on COBOL-68's primary decimal data types: strings of up to 100 digits, with one EBCDIC or ASCII digit character or two 4-bit binary-coded decimal BCD digits per byte. Portable COBOL programs did not use binary integers at all, so the B2500 did not either, not even for memory addresses. Memory was addressed down to

86-493: A 1-microsecond cycle time. B2500/3500 weighed about 600–700 pounds (270–320 kg). The B2500/B3500 machines were followed by B2700/B3700/B4700 in 1972; The B2800/B3800/B4800 in 1976, The B2900/B3900/B4900 in 1980 (which was the first of the range to load its microcode from floppy disk , rather than implementing it as hardware read-only memory ) and finally the Unisys V Series machines V340-V560 in 1985-90. Machines prior to

129-622: A Belgian bank was still using EBCDIC internally in 2019. A customer insisted that the correct spelling of his surname included an umlaut , which the bank omitted, and the customer filed a complaint citing the guarantee in the General Data Protection Regulation of the right to timely "rectification of inaccurate personal data." The bank's argument included the fact that their system used EBCDIC, as well as that it did not support letters with diacritics (or lower case, for that matter). The appeals court ruled in favor of

172-535: A library/backup device that contained all the data files and sometimes the program files (using the MFSOLT utility ) for a particular application or customer/client. COBOL to machine code Tape resident disk files Job headers for card input Card and print spooling I did accounting system (parameter driven) —a blank verse by unknown B2500 user EBCDIC Extended Binary Coded Decimal Interchange Code ( EBCDIC ; / ˈ ɛ b s ɪ d ɪ k / )

215-624: A manner specified by IBM's Character Data Representation Architecture (CDRA). Although the default mapping of New Line (NL) corresponds to the ISO/IEC 6429 Next Line (NEL) character (the behaviour of which is also specified, but not required, in Unicode Annex 14), most of these C1-mapped controls match neither those in the ISO/IEC 6429 C1 set , nor those in other registered C1 control sets such as ISO 6630 . Although this effectively makes

258-432: A series of legendary television commercials featuring Ella Fitzgerald . In the commercials, she would sing a note that shattered a glass while being recorded to a Memorex audio cassette . The tape was played back and the recording also broke the glass, asking "Is it live, or is it Memorex?" This would become the company slogan which was used in a series of advertisements released through 1970s and 1980s. In 1982, Memorex

301-446: A single 300,000 digit address space. Later machines had separate million-digit spaces for program code and process data. Instructions' address fields were extended from five digits to six digits, and four more real index registers were added. Early machines used Burroughs's head-per-track disk systems rather than the now-standard movable head platter disks. In one attempt to speed up MCP, its overlays were carefully laid out so that

344-499: A time, beginning with most-significant digits then working rightwards to least-significant digits. This is backwards from manual right-to-left methods and more complicated, but it allowed all result writing to be suppressed in overflow cases. Serial arithmetic worked very well for COBOL. But for languages like FORTRAN or BPL, it was much less efficient than standard word-oriented computers. Three reserved memory locations were used as address indexing 'registers'. The third index register

387-453: Is a prerequisite for doing page style virtual memory when operands cross page boundaries.) The machine matched COBOL so closely that the COBOL compiler was simple and fast, and COBOL programmers found it easy to do assembly programming as well. In the original instruction set, all operations were memory-to-memory only, with no visible data registers. Arithmetic was done serially, one digit at

430-423: Is an eight- bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems. It descended from the code used with punched cards and the corresponding six-bit binary-coded decimal code used with most of IBM's computer peripherals of the late 1950s and early 1960s. It is supported by various non-IBM platforms, such as Fujitsu-Siemens ' BS2000/OSD , OS-IV, MSP, and MSP-EX,

473-540: The SDS Sigma series , Unisys VS/9 , Unisys MCP and ICL VME . EBCDIC was devised in 1963 and 1964 by IBM and was announced with the release of the IBM System/360 line of mainframe computers . It is an eight-bit character encoding, developed separately from the seven-bit ASCII encoding scheme. It was created to extend the existing Binary-Coded Decimal (BCD) Interchange Code, or BCDIC , which itself

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516-600: The Telex Corporation becoming Memorex Telex NV, a corporation based in the Netherlands , which survived as an entity until the middle 1990s. The company evolved into a provider of information technology solutions including the distribution and integration of data network and storage products and the provision of related services in 18 countries worldwide. As late as 2006, several pieces existed as subsidiaries of other companies, see e.g., Memorex Telex Japan Ltd

559-446: The 1970s and into the early 1980s, Memorex was worldwide one of the largest independent suppliers of disk drives and communications controllers to users of IBM-compatible mainframes, as well as media for computer uses and consumers. The company's name is a portmanteau of "memory excellence". Memorex entered the consumer media business in 1971 and started the ad campaign, first with its "shattering glass" advertisements and then with

602-454: The 4-bit digit in big-endian style, using 5-digit decimal addresses. Floating point numbers also used base 10 rather than some binary base, and had up to 100 mantissa digits. A typical COBOL statement ' ADD A, B GIVING C ' may use operands of different lengths, different digit representations, and different sign representations. This statement compiled into a single 12-byte instruction with 3 memory operands. Complex formatting for printing

645-640: The B4800 had no cache memory . Every operand byte or result byte required its own separate main memory cycle, which limited program performance. To compensate for this, the B3700/B4700 generation used semiconductor main memory that was faster but more expensive and power hungry than the DRAM used in competing machines. The unusual use of decimal numbers as memory addresses was initially no problem; it merely involved using 1-in-5 rather than 1-in-8 decoder logic in

688-576: The EBCDIC character set are made in the 1979 computer game series Zork . In the "Machine Room" in Zork II , EBCDIC is used to imply an incomprehensible language: This is a large room full of assorted heavy machinery, whirring noisily. The room smells of burned resistors. Along one wall are three buttons which are, respectively, round, triangular, and square. Naturally, above these buttons are instructions written in EBCDIC... In 2021, it became public that

731-606: The EBCDIC variants and how to convert between them is still internally classified top-secret, burn-before-reading. Hackers blanch at the very name of EBCDIC and consider it a manifestation of purest evil. EBCDIC design was also the source of many jokes. One such joke, found in the Unix fortune file of 4.3BSD Reno (1990) went: Professor: "So the American government went to IBM to come up with an encryption standard , and they came up with—" Student: "EBCDIC!" References to

774-590: The MCP and also by some application programmers. Later versions discontinued this and instead supported two new opcodes (binary to decimal and decimal to binary) to support addressing the hard drives available after Burroughs's acquisition of Memorex . Unisys cancelled further V series hardware development in 1991, and support ended in 2004. In the B4900 and later machines, integer operations of 10 digits or fewer were now handled in parallel; only longer operands continued to use

817-499: The MCP of Burroughs' Large Systems stack machines, but was entirely different internally, and was coded in assembly language , not an ALGOL derivative. Programs had separate address spaces dynamically relocated by a base register , but otherwise there was no virtual memory ; no paging and no segmentation . Larger programs were squeezed into the limited code address space by explicit overlays . The nonresident parts of MCP were also heavily overlaid. Initially, code and data shared

860-469: The absence of several ASCII punctuation characters fairly important for modern computer languages (exactly which characters are absent varies according to which version of EBCDIC you're looking at). IBM adapted EBCDIC from punched card code in the early 1960s and promulgated it as a customer-control tactic (see connector conspiracy ), spurning the already established ASCII standard. Today, IBM claims to be an open-systems company, but IBM's own description of

903-408: The absence of use for other purposes), so this mapping is permissible in, but not specified by, Unicode. The following code pages have the full Latin-1 character set (ISO/IEC 8859-1). The first column gives the original code page number. The second column gives the number of the code page updated with the euro sign (€) replacing the universal currency sign (¤) (or in the case of EBCDIC 924, with

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946-492: The chips, and done again for each cache or memory cycle. This conversion logic slowed the machine cycle somewhat. An attempted redesign in 1975 of the address space was called MS-3 for "Medium Systems 3rd Generation", but that project was cancelled. Machines before the B2900 allowed input numbers with 'undigit' values above 9, but arithmetic on this gave unspecified results. This was used as a form of hexadecimal arithmetic within

989-683: The company did not have time to prepare ASCII peripherals (such as card punch machines) to ship with its System/360 computers, so the company settled on EBCDIC. The System/360 became wildly successful, together with clones such as RCA Spectra 70 , ICL System 4 , and Fujitsu FACOM, thus so did EBCDIC. All IBM's mainframe operating systems , and its IBM i operating system for midrange computers , use EBCDIC as their inherent encoding (with toleration for ASCII, for example, ISPF in z/OS can browse and edit both EBCDIC and ASCII encoded files). Software can translate to and from encodings, and modern mainframes (such as IBM Z ) include processor instructions, at

1032-482: The compiler, which was released in 1982. MCP allowed programs to communicate with each other via core-to-core transmissions ( CRCR ) or by using storage queues ( STOQ ), implemented as system calls using the BCT instruction and exposed to the languages (COBOL FILL FROM/INTO ). This was unheard of except on the very largest IBM System/360 systems of the time, and even then it was a major operational headache to manage

1075-410: The core memory's row selects and bank selects. But later machines used standard memory chips that expected binary addresses. Each 1000-byte block of logical memory could be trivially mapped onto a subset of 1024 bytes in a chip with only 2.3% waste. But for denser chips and larger total memories, the entire decimal address had to be crunched into a shorter quasi binary form before sending the address to

1118-719: The customer. Memorex Memorex Corp. began as a computer tape producer and expanded to become both a consumer media supplier and a major IBM plug compatible peripheral supplier. It was broken up and ceased to exist after 1996 other than as a consumer electronics brand specializing in disk recordable media for CD and DVD drives, flash memory , computer accessories and other electronics . Established in 1961 in Silicon Valley , Memorex started by selling computer tapes, then added other media such as disk packs. The company then expanded into disk drives and other peripheral equipment for IBM mainframes . During

1161-506: The hardware level, to accelerate translation between character sets. Not all operating systems running on IBM hardware use EBCDIC; IBM AIX , Linux on IBM Z , and Linux on Power all use ASCII, as do all operating systems that run on the IBM Personal Computer and its successors. There were numerous difficulties to writing software that would work in both ASCII and EBCDIC. There are hundreds of EBCDIC code pages based on

1204-402: The interactions of the multiple program streams. The Medium Systems series were very effective multi-programming machines. Even very basic versions of the B2500 could support multiprogramming on a usable scale. Larger Medium Systems processors supported major data center activities for banks and other financial institutions, as well as many businesses and government customers. The Medium System

1247-567: The invariant subset works only for languages using the ISO basic Latin alphabet , such as English (excluding loanwords and some uncommon orthographic variations) and Dutch (if the "ij" and "IJ" ligatures are written as two characters). Following are the definitions of EBCDIC control characters which either do not map onto the ASCII control characters , or have additional uses. When mapped to Unicode, these are mostly mapped to C1 control character codepoints in

1290-437: The likely-next overlays would soon arrive at their read head just after the current overlay completed. This was similar to time-dependent layout optimizations on early delay-line and drum computers. But this turned out to be impractical to maintain after software changes, and better results were consistently achieved with a totally randomized layout of all MCP overlays. Other than the operating system itself, all system software

1333-706: The non-ASCII EBCDIC controls a unique C1 control set, they are not among the C1 control sets registered in the ISO-IR registry, meaning that they do not have an assigned control set designation sequence (as specified by ISO/IEC 2022 , and optionally permitted in ISO/IEC 10646 (Unicode)). Besides U+0085 (Next Line), the Unicode Standard does not prescribe an interpretation of C1 control characters, leaving their interpretation to higher level protocols (it suggests, but does not require, their ISO/IEC 6429 interpretations in

Burroughs Medium Systems - Misplaced Pages Continue

1376-469: The original EBCDIC character encoding; there are a variety of EBCDIC code pages intended for use in different parts of the world, including code pages for non-Latin scripts such as Chinese, Japanese (e.g., EBCDIC 930, JEF, and KEIS), Korean, and Greek (EBCDIC 875). There is also a huge number of variations with the letters swapped around for no discernible reason. The table below shows the "invariant subset" of EBCDIC, which are characters that should have

1419-584: The same assignments on all EBCDIC code pages that use the Latin alphabet. (This includes most of the ISO/IEC 646 invariant repertoire, except the exclamation mark .) It also shows (in gray) missing ASCII and EBCDIC punctuation, located where they are in Code Page 37 (one of the code page variants of EBCDIC). The blank cells are filled with region-specific characters in the variants, but the characters in gray are often swapped around or replaced as well. Like ASCII,

1462-416: The serial method. And all floating point operations were limited to 17 digits of precision. Later Medium Systems machines added an accumulator register and accumulator/memory instructions using 32-bit, 7-digit integers and 48-bit or 80-bit floating point values, all aligned on 16-bit word boundaries. The operating system was called MCP, for Master Control Program. It shared many architectural features with

1505-534: The set changed to match ISO 8859-15 ) Different countries have different code pages because these code pages originated as code pages with country-specific character repertoires, and were later expanded to contain the entire ISO 8859-1 repertoire, meaning that a given ISO 8859-1 character may have different code point values in different code pages. They are known as Country Extended Code Pages ( CECP s). Open-source software advocate and software developer Eric S. Raymond writes in his Jargon File that EBCDIC

1548-510: Was accomplished by executing a single EDIT instruction with detailed format descriptors. Other high level instructions implemented "translate this buffer through this (e.g. EBCDIC to ASCII) conversion table into that buffer" and "sort this table using these sort requirements into that table". In extreme cases, single instructions could run for several hundredths of a second. MCP could terminate over-long instructions but could not interrupt and resume partially completed instructions. (Resumption

1591-462: Was bought by Burroughs for its enterprise businesses; the company’s consumer business, a small segment of the company’s revenue at that time was sold to Tandy. Over the next six years, Burroughs and its successor Unisys shut down, sold off or spun out the various remaining parts of Memorex. The computer media, communications and IBM end user sales and service organization were spun out as Memorex International. In 1988, Memorex International acquired

1634-566: Was coded in BPL (Burroughs Programming Language), a systems programming language derived from ALGOL and Large System's ESPOL systems language. The initial COBOL compiler supported the ANSI 68 specification and supported the ENTER SYMBOLIC syntax to allow inline assembly language coding, but lacked support for RELATIVE and INDEXED file support; these were later added into the ANSI 74 version of

1677-416: Was dedicated to pointing at the current procedure's stack frame on the call/return stack. Other reserved memory locations controlled operand sizes when that size was not constant. The B3500 was similar to the B2500 but with a faster cycle time and more expansion choices. The B2500 had a maximum of 60 K bytes of core memory and a 2 microsecond cycle time. The B3500 had a maximum of 500 K bytes and

1720-464: Was devised as an efficient means of encoding the two zone and number punches on punched cards into six bits. The distinct encoding of 's' and 'S' (using position 2 instead of 1) was maintained from punched cards where it was desirable not to have hole punches too close to each other to ensure the integrity of the physical card. While IBM was a chief proponent of the ASCII standardization committee,

1763-439: Was loathed by hackers, by which he meant members of a subculture of enthusiastic programmers. The Jargon File 4.4.7 gives the following definition: EBCDIC: /eb´s@·dik/, /eb´see`dik/, /eb´k@·dik/, n. [abbreviation, Extended Binary Coded Decimal Interchange Code] An alleged character set used on IBM dinosaurs. It exists in at least six mutually incompatible versions, all featuring such delights as non-contiguous letter sequences and

Burroughs Medium Systems - Misplaced Pages Continue

1806-492: Was not unusual to be running eight or ten programs on a medium-size B2500. Medium System installations often had tape clusters (four drives integrated into a mid-height cabinet) for magnetic tape input and output. Free-standing tape drives were also available, but they were much more expensive. Tape was a major storage medium on these computers, in early days it was often used for father-son batch updating; with additional disk becoming cheaper as time moved on it became relegated as

1849-480: Was the preferred platform for many data processing professionals. With the Medium System, a computer could be simultaneously running a batch payroll system, inputting bank checks on a MICR reader sorter, compiling COBOL applications, supporting on-line transactions, and doing test runs on new applications (colloquially called 'the mix', as the console command ' MX ' would shows that jobs were executing). It

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