IBM 604

The IBM 604 was a control panel programmable Electronic Calculating Punch introduced in 1948 [ [http://www-03.ibm.com/ibm/history/history/year_1948.html IBM Archive: 1948] ] , and was a machine on which considerable expectations for the future of IBM were pinned and in which a corresponding amount of planning talent was invested.

Most of the circuitry was based on modifications of circuit designs used in the earlier 603 Electronic Multiplier and was packaged in small one-tube-replaceable pluggable units. The calculation unit contained 1,400 tubes. Clock speed was increased from the 603's rate of 35kHz to 50kHz. The 604 performed fixed point addition, subtraction, multiplication and division using BCD arithmetic.

Initial versions supported 40 program steps, but this was soon expanded to 60. Processing was still locked to the reader/punch cycle time, thus program execution had to complete within the time between a punched card leaving the read station and entering the punch station.

The 604 and a modified version, the 605, were used as components of the Card Programmed Electronic Calculators (CPC and CPC II). The 604 was also a component of the "Test Assembly", a precursor to IBM's early computers [ cite journal
last = Bashe
first = C.J.
coauthors = et al.
title = The Architecture of IBM's Early Computers
journal = IBM J. Res & Develop.
volume = 25
issue = 5
date = September, 1981
url=http://www.research.ibm.com/journal/rd/255/ibmrd2505C.pdf] .

"See also": List of IBM products.

References

* [http://ed-thelen.org/comp-hist/IBM-604.html IBM 604 Electronic Calculating Punch -- notes, manuals]
*cite book
last = IBM
title = IBM 604 Electronic Calculating Punch: Manual of Operation
id = 22-5279-10
date = 1954
url = http://www.bitsavers.org/pdf/ibm/604/22-5279-10_604_OperMan.pdf
*cite book
last = IBM
title = IBM Customer Engineering Manual of Instruction: 604 Electronic Calculating Punch
id = 227-7609-0
date = 1958
url = http://www.bitsavers.org/pdf/ibm/604/227-7609-0_604_CE_man_1958.pdf

External links

*cite book
first = Martin H.
last = Weik
title = A Third Survey of Domestic Electronic Digital Computing Systems: IBM 604 Section
publisher = Ballistic Research Laboratories (BRL)
date = March 1961
id = Report No. 1115
url = http://ed-thelen.org/comp-hist/BRL61-ibm06.html#IBM-604 Contains about 4 pages of IBM 604 survey detail: applications, customers, specifications, and costs.
* [http://www.science.uva.nl/faculteit/museum/604.html University of Amsterdam: Computer Museum, IBM 604]

Notes