Autocoder

Autocoder was the name given to certain assemblers for a number of IBM computers of the 1950s and 1960s.The first Autocoders appear to have been the earliest assemblers to provide a macro facility. [Solomon 1993, p. 8.]

The term "autocoder" needs to be distinguished from "autocode", a term of the same era which was used in the UK for languages of a higher level. Both terms derive from the phrase "automatic coding", which referred generally to programs which eased the burden of producing the numeric machine language codes of programs. [Hopper 1955.] ("Autocoding" is seen occasionally, and can refer to any kind of programming system.) In some circles "autocoder" could be used in a rather generic way to refer to what is now called a macroassembler. [For an example see Allen 1981, p. 540.]

The first Autocoders were released in 1955 for the IBM 702 and in 1956 for the almost compatible IBM 705. They were designed by Roy Goldfinger who earlier had worked on New York University's (NYU) NYAP assembler. [Goldfinger 1956.] [ [http://hopl.murdoch.edu.au/showlanguage.prx?exp=2989 The Encyclopedia of Computer Languages ] ] These machines were variable word length commercial machines, as were many of the computers for which an Autocoder was released.

Besides the 702 and 705, there eventually also were Autocoders for the IBM 7010, IBM 7030 (Stretch), IBM 7070, IBM 7080, and the IBM 1400 series. [7010: Weik 1964, p. 0160; 7030: [http://www.brouhaha.com/~eric/retrocomputing/ibm/stretch/] , [http://www.cgo.org/cgo2003/keynote/FranAllenCGO.pdf] ; 7070: [http://www.multicians.org/thvv/7070.html] , [http://ed-thelen.org/comp-hist/BRL61-ibm7070.html] ; 7080: [http://www.research.ibm.com/journal/sj/052/ibmsj0502B.pdf] ; 1400 series: [http://www-03.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology2.html] , [http://bitsavers.org/pdf/ibm/14xx/C28-0309-1_1410_autocoder.pdf] . ] Other manufacturers sometimes built competing products, such as NCR's "National's Electronic Autocoder Technique" (NEAT). [Weik 1964, p. 0202.]

The most well known Autocoder is that of the IBM 1401, undoubtedly due in part to the general success of that series of machines. Autocoder was the primary language of this computer, and its macro capabilities supported use of the Input/Output Control System which eased the programming burden. [ [http://archive.computerhistory.org/resources/text/IBM/IBM.1440.1962.102646251.pdf] ; Solomon 1993, p. 8; [http://hopl.murdoch.edu.au/showlanguage2.prx?exp=3872] .] Another assembler, Symbolic Programming System (SPS), was also available for the 1401 and used the same mnemonics but a different input format. It lacked Autocoder's features and was generally used only on machines with less than the minimum 4000 characters of memory needed to use Autocoder. [ [http://ed-thelen.org/comp-hist/ibm-1401.html] , [http://www.multicians.org/thvv/1401s.html] .]

Notes

References

* Allen, F. E., "The history of language processor technology at IBM", "IBM Journal of Research and Development," 25(5), pp. 535-548 (September 1981). [http://www.research.ibm.com/journal/rd/255/ibmrd2505Q.pdf]
* Goldfinger, Roy, "The IBM Type 705 Autocoder". "Proceedings East Joint Computer Conf.," San Francisco, 1956.
* Hopper, Grace, "Automatic Coding for Digital Computers" in the High Speed Computer Conference, Louisiana Stat (1955) the High Speed Computer Conference, Louisiana State University, 16 Feb. 1955, Remington Rand, Inc., 1955. [http://www.bitsavers.org/pdf/univac/HopperAutoCodingPaper_1955.pdf]
* Salomon, David, "Assemblers And Loaders" (Horwood, 1993), ISBN 0130525642. [http://www.davidsalomon.name/assem.advertis/AssemAd.html]
* Weik, Martin H., "A Fourth Survey of Domestic Electronic Digital Computing Systems,"BRL Report No. 1227, January 1964 (Ballistic Research Laboratories, Aberdeen Proving Ground, Maryland). [http://ed-thelen.org/comp-hist/BRL64-i.html]

External links

* [http://www.bitsavers.org/pdf/ibm/14xx/C24-3319-0_1401_tapeAutocod.pdf 1964 IBM 1401 and 1460 Autocoder manual from Bitsavers]
* [http://bitsavers.org/pdf/ibm/14xx/C28-0309-1_1410_autocoder.pdf 1964 IBM 1410 Autocoder manual from Bitsavers]
* [http://99-bottles-of-beer.net/language-assembler-(1401-autocoder)-1071.html IBM 1401 Autocoder example]